The Miami Heat visiting team bench will be directly behind section 106, which is on the same side of the arena as your section (209). From section 209, you will be closely aligned to the Heat bench as you are near mid court, and more towards the side where the Heat bench will be. If you think your son would rather be on the opposite side from the bench to be able to see the Heat players faces, you could consider some of the closer rows in section 225. However from section 209, you will certainly be in the closest 200 level section to the visiting team.

Section 209 Seating Location Versus Visitor Bench at Time Warner Cable Arena
Section 209 will be one of the closer upper level sections to the visiting team bench, but head on views of the players will be better on the opposite side of the arena