-Spoiler-
Probably still not high enough. Have you invited him to the fair? Gave him exotic coffee? Usually I spam that to him as well as give his sister some dildos until the 'likes you more' notification stops so they both join me when fighting their mom. There's a few more things but I think very high likes is enough to sway him to your side. Can you vent your troubles to him in your dialogue?
I had him at 100 like and still he sided against me I then went to his character profile under the relationship tab and made sure I did all the talk, quest and gift options included all 3 Everett visiting scenes ( last one you can join their fun), the love potion scene and all vent dialog ( more get added as more characters and quests are done)
