Ok, let's assume the financial offer was perfect for him and it was only about minutes then.
There is only 1 thing that decides about playing time under Pep (if fit), you simply have to show you are better than your team mates.
Any player has to show that, in training and on the pitch, then Pep would pick him.
Not regularly of course under our concept of rotation in 4 competitions, but between 3,500 and 4,000 minutes per season, for a forward/winger.
Leroy can't "wait" to see if he get's minutes, he has to deliver any single day - burning desire. Ask Pep.
That's what he has to do to find out if he gets in the team as you say.
It seems it wasn't enough somehow last season, even compared to Mahrez, not to Raz and Bernardo.
That's why I would prefer to assume there indeed were financial reasons, because the other option would be much worse:
it would be a long standing secret agreement between Leroy and BMU, and we shouldn't even think about that.