Is there a downside to clearing a hard level with the help of multiplayer?

I’m new to Splatoon and I’m struggling hard with the postgame. I’m at lv 90 of the bottomless pit, I wanna at least clear lv 100 for the outfit, but the final 10 levels just seem impossible.

Is there a penalty for getting others to help me clear it? It feels like cheese, having 4 people instead of 1. Do I get less treasure? Does it not count towards completion? Is there anything else I need to know?