Motivation might give Milan an extra boost, but I would still be more cautious about betting on a Milan win. Lecce shouldn't be underestimated, and based on their previous match, they managed to draw against Genoa away from home. Genoa had always beaten Lecce in their last 5 encounters. Meanwhile, Milan recently played at home but were defeated by a newly promoted serie A team. So in my opinion, betting on a Milan win is a bit more risky, and I would prefer to bet on BTTS (Yes)
Hoping for both teams to score is also a good option. However, I also have my doubts about BTTS. Betting on an AC Milan win isn't guaranteed to pay off either. So I'd probably prefer to pass on this match. Betting on a team with inconsistent and uncertain performance is very risky. I'd probably prefer to bet on another, more predictable match, even if the outcome isn't guaranteed to be as expected.
If AC Milan loses again against Lecce, it will only worsen their situation. The players' mentality won't be good either. Therefore, AC Milan must win this match. Allegri, who was expected to bring significant improvements to AC Milan, is probably under considerable pressure right now. After all, seeing a team that has prepared so meticulously lose at home so early in the season must be truly embarrassing.