I think it's at least worth noting that having played like garbage for the entire first half (outside the game's first 6 minutes where their defense was on lock), and getting booed by their own fans as they left for halftime, the Sixers turned it around and wore the Heat down throughout the second half. While their comeback getting completed may have been down to Nic Batum suddenly hitting all his threes, they played a lot better on both ends of the court and created the opportunity where they only needed a little luck to save them.
Embiid didn't have the energy for very many drives, but the ones he did have were generally pretty successful. Paul Reed did a pretty good job of rim-protecting while Embiid was out, including some blocks and altered shots. With one exception I can think of (Butler all alone in the corner), all the outside shots Philadelphia conceded were decently contested, and they slowed the fast break points that had killed them in the first half down to a trickle. They still struggled against the zone for most of the 3Q, but were able to get it in rotation a few times, draw a foul a few times, and went from "looks like they've never seen one before", in the first half, to "semi-effective against it" in the second half.
Some decent coaching by Nick Nurse in that game, which made up for the lack of preparation that seemed apparent and could also be laid at Nurse's feet, but still, they got it done.
(and if the game was 3 seconds longer, the Heat would've had a shot to win it at the buzzer, as a Maxey/Embiid confusion on the final inbounds got deflected for a turnover... but the clock ran out)