[2020] Constant 9.3

No.

As far as I remember, if you play with friend in squad, you will face someone else in similar squad (so friend squad, not random squad) in enemy team. That's all. No different BR pool etc. And of course higher BR in squad counts, so if your friend got vehicle with, for example BR 0.3 higher than your max, MM will search battle with his BR, not yours.