Just to add a wee bit to my above semi rant. I have had the pleasure of playing a part in about apprentices. Some of which I have had for the full term others i have picked up as they were struggling with their spark and close to being chucked by the firm i worked for...as long as they showed willing I would take them on and turn them round. One lad was trained by the roughest git alive...poor kid, i must have spent 3 months telling him "rip it out lad do it properly". That boy has his own little firm now and employed 5 lads.
It's been 5 years since my last one. Im not in the game full time any more but im pretty proud to have taken a small amount of time to "give back" regardless of the company involved. At the end of the day if grown men hadn't taken the time to show me then where would I have been. Im pretty sure most of us didn't come out of school as fully trained sparks lol.
OP you could give the lad some advice and tell him how to ride this out and finish his apprenticeship after which he can start afresh full of knowledge somewhere new. It's a big old world out there. Also maybe point out that if the lad isnt trained in some aspects then they should rectify that as per the conditions of any grants they will be receiving to employ this lad.