Jrisebo:
I’d stay out of that garage and a long way away from that project. It’s a disaster well on its way to happening, and you don’t want to be involved when it happens. You might report that to the local Bldg. Dept. and have them look into it, if they wish. You can’t cut out the bottom three quarters of a 14 or 16" deep truss, leaving only the top chord intact, over the middle third of the span, however you try to reinforce it, without causing problems. The photo already has an appropriate sign at the bottom right corner, and he’s too dumb to heed it, the WARNING. You can educate ignorance away, you really can’t fix stupidity.