It comes down to this
KO and Leonard force Howard out the paint and ultimately out of the game, which is more significant than you think. Having Bam out there keeps Howard on the floor and plays into what the lakers want
AD chasing KO around opens up the paint more for a Jimmy as well.
ultimately, because neither KO or Leonard can guard AD one on one like Bam. Spo immediately is sending doubles. While AD can pass out of it, he can’t do it on a whim like Bron to his target in their place to take the best shot they can. This puts Kuzma etc in a uncomfortable place. Him and Morris were decent but the lakers offense were thrown out of whack, along with AD getting in foul trouble.
Forcing the other lakers to beat them is what the Heat want and they have more bodies to throw at Bron(Butler Iggy Jae) than they do AD.
I expect Frankie V to adjust pretty well for this, but outside of rebounds, The Heat having a extra shooter on the floor in Leonard and Kelly playing extra minutes is actually better suited for this matchup. Bam, as good as he is, is a non shooting big that allows Howard to stay on the floor with AD and pack the paint, which has been one of the Lakers strong points defensively. Ad + another big just suffocating everyone who looks to drive
when Bam does come back, I immediately expect a line up from Spo of
Bam
Kelly
Crowder
Butler
Herro/Duncan
One player to keep AD out the paint while Bam goes up against Howard. I hope Vogul is prepared.