Help! Some of the small flower buds that appeared ...

I'm not too sure who is breeding cannabis plants with genetic modifications to make them immune to pests, so not sure how much of an option that is. BT is what you want. Much easier to get hold of a product with that in it. Specifically, Bacillus thuringiensis kurstaki. It's a bacteria that will kill the caterpillars that try to eat your plant, but it needs to be given to the plant in veg to uptake before flower. It mainly targets caterpillars, so it won't kill any beneficial bugs you might have around. You can read about it more here https://en.wikipedia.org/wiki/Bacillus_thuringiensis_kurstaki Also, do not spray into the hole the caterpillar made, water sitting in a wound of a plant in flower is a recipe for disaster.

I agree with Shinsimilla, need to cut it away, looks like a burrowing type of worm that will keep eating away at it. I know of such bugs that affect the squash family of vegetables. The beetles come in, bite a hole. lay a egg and fuck off, then the egg hatches and eats the squash stem from the inside out causing great damage to the plant and its fruits. Preventive pesticides are the only real way to deal with them, or GMO plants that have stuff in their genes to kill the bugs if they eat it. Hopefully they are done laying eggs the the trimming of plants won't be so bad. You could try spraying pesticide into the hole they are in if you don't want to trim but that might cause it to rot out. the buds aorund that area should not be consumed. Good Luck!

Oh no, unfortunately this is rather bad news. You need to cut that out asap. The worm poo and wounds on the plant often causes budrot, but smoking worm shit isn't great anyway. Whatever you lose now will be less than if you wait any longer. Like you saw they like to eat the stem and the whole bud dies, so cut off a little more than you think you need to, to make sure you get all the worms. I have dealt with them a few times and they are a pain in the ass. It's a bit late now, but you can give your plants BT in future. It helps them build up resistance to them.