I sympathise, I've been there myself:(
I sent one gelding to a younger unknown trainer, in under 60 days he was trail safe and it cost me not even $1000.
His half brother I sent to a well known recommended trainer who completely screwed him up, he was returned to me(after a bit of a em discussion)un rideable, with girth galls and saddle sores after just under 60 days, cost me $1800 for a train wreck, 6 months to heal up and the following year I sent him to another trainer who did a great job in a short time as I couldn't afford much:(
It's a bit of a lottery with trainers I'm afraid.
Glad your boy is getting better:)