I'm sorry to say it is bud rot. It doesn't seem to extensive. And it's a mold, with spores, so it can and will spread, and it looks like you have a few weeks to go.
There are options. It's not a total loss...Not IMO anyways. Some people would chuck the whole thing.
You probably should cut the buds off that have noticeable rot, and get them away from the plant. If you want to dissect them and smoke what's not nasty looking, that's up to you, but it's not the healthiest stuff...Or you could use it for other things. But don't play with it around your plant.
And I normally don't defoliate, but in a wet year like this, and this late in the game, I'd peel off most of the fan leaves so it can breath. That's what I did on mine and they are still going.
Regalia CG is a great organic product but it's more of a preventative and even it is not a guarantee, but check it out for next year.
Beautiful plant, and good luck...Hopefully the weather cooperates!