Most likely bacterial canker for sure. My best sweet cherry is 'burlat' which responds very well to disease pressure in this area. I can also see problems associated with having cherry trees with too many grafts on and also too much mid-day sunshine verses the ratio of being watered. 

Even if you used the proper spraying routines, sprays are only of value when the underlying condition (per the above) are met. Also I am not sure where you found oils would work on these cases, but I guess that's why your here, but they won't work for this bacterial gummosis.

I am still learning too so nobody's perfect.

You bring up some good points that make me think a bit deeper. Then lets start with a better diagnosis first. So -had you cut any branches away to expose too much sun to the trunk or done any landscaping recently that might have cut roots? If the answer is yes, then I suggest that the tree is recoverable and you can use this start of a dry period to cut away the active bacteria that is bruising the trunk. For these picture helps (if they help) go to the following link.

https://pnwhandbooks.org/plant.....ial-canker

There are other web sites by OSU that give pictures of the bacteria effecting twigs after rain and after weather cools in the fall of which we are wanting to see which cultivars are more well suited. The worst of which could be removed in favor of the more suited cultivars. Because young cherry trees do go through a difficult first few years with this kind of thing. Well watering in the dry of summers will do more to bring cherry past this familiar battle than any spray program will. And the proper more resilent choice of cultivars always also are better than any spray program. All these online recommendations are for commercial acres of trees and have never been proven in these yard situations. 

I have some of this as seen in your pictures and the link pictures above now in my old burlat cherry now that I excavated and tore away a side root. I also accidentally removed a sunward branch that caused shock to the trunk exposure. Mine looks worse than yours now but the cultivar will survive with more mid-summer water and because the cultivar is strong. I have never sprayed any cherry trees I have.

My experience with my 'blackgold' sweet cherry /gisela-5 dwarfing stock from Raintree went the same way. The years with more summer water the better it would be year over year. You can't really say it's bacterial gummosis because then your not paying attention to the real issues of hydraulic failure of the vessels during hot weather. It took many years of doing what you are to finally get my tree back into order. Some years in the fall when I could tell I was about to lose it then I would resort to removing all the verticle growth of the central leader so that I could shelter winter rains away from the remaining branches. It clung onto life without any spraying. It was just a matter of time for the tree to rebuild into the nearby 20 year old compost pile that was next or near to it. I gave up on using a shelter ever 2nd year so I rebuilt the central leader with a roadside cross of a sweet cherry x the wild bitter cherry, and at which point I was aiming at shading the suseptable branches from the harming summer suns detrimental effects.

At this time the whole tree is very healthy due to a more disease resistant hybrid than what the blackgold was. The blackgold is still there as an interstock with very small branches that are still alive. But you can't ask me what's going on inside, this is still mostly lots of guessing for the experts.

The idea that I have on removing the most suseptable cultivars you have in favor of the resilent seems to sort of stem from many other places such that multigrafted trees with several cultivars grafted at once on the same tree is too.much for the immune system of the tree to figure out. Each different branch are more hypersensitive to a particular pathogen then others others are for one particular pathogen. 

OSU continues to show publications if sweet cherry sensitivity as while young they adjust the proper immunity. Up north in disasterously cold climates the old scientist (now dead) would refer to the impossibility of growing any fruit tree say in Idaho for a year and then transfer it to Alaska's shorter and then followed by cold season. They need time to think what to do even if it is in our case a single graft that is slightly confusing.

You could always try copper sprays in lieu of a shelter against bacterial gummosis. In dryer areas you can also remove the bruising followed up by sterilizing. I haven't. I have probably had to do extreme things in the past and have not so I lost my first sweet cherry from raintree 'angela' /gisela-5, though the rootstock came up and I toy graft to those. I have had the same wild hybrid fruit well on it only to have people walk by and grab the braches and destroying the graft.

If it's not birds it's people, but I still get my cherries by netting.

I can't say for sure which in the above 3 cherry pictures I took today are the least or the most prone to bacterial gummosis because my watering strategies that I use in my yard were not the same. I do know that using more resistant cultivars is the leading method of choice above all else by the institutions breeding fruit trees.

I am glad what I said makes sense. Of course you and I (like any 2 persons) go about ways of treating things in different ways. A third option not being discussed almost breaking news (maybe last couple years) is that certain bacteria in the ground manufacture medicine for plants and for everything in our fruit world of trees. It means that as the bad bacteria try thriving in the stressed and injured areas of the tree the good bacteria in the ground are there to rectify the problem specifically.

Which is more an area that I have not experimented with (so that's John S' area) until recently when I bought 10 pounds of pure wettable powder bacteria. I am supposed to use that as a soil drench.

Thanks.