Seroquel XR and Guanfacine combo? | ADHD Information

My soon to be 7yo son has been diagnosed ADHD with possible mood
disorder and his doctor (whom I do like and has helped us alot) has had
him on Seroquel XR and he also takes Guanfacne 2mg 3X per day.

Anyone else ever been on this combo or heard of it??

We have tried 2 stims in the past, one did nothing (I think it was concerta)
and one gave him violent and horrible motor tics (Vyvanse).

He is still having trouble listening, focusing, following directions,
remembering things, but is not as hyperactive as he's been in the past.

Anyone have a similar experience or input? I have seen the commercials
on TV that Seroquel is a medicine designed for people with BiPolar
disorder (which he probably doesn't have), but his doctor continues to
prescribe it to him.

Thanks!