TL;DR does your Pokémon level matter while doing Max Raids? Is there any reason for having them sometimes fill at the instant they are available but other times literally nobody joins? Best way to catch Pokémon there?

Could someone help me understand wi-fi Battle Max Raids? From my understanding, it's one person requesting help, and there can join (if my Pokémon has a type advantage over the Pokémon on the raid. Yes I know this isn't necessary but I'd rather have it), do my Pokémon stats make any difference if I bring a level 60 (fully EV trained) vs a level 100 fully EV trained?

Whenever I request assistance mostly I get is one person helping :'( and the remaining have to be NPCs yes we beat the thing but it's not as fun as getting help from 3 other people.

Yet when I see someone requesting help, most of the time the thing gets full while I am trying to connect.

Finally, after beating the thing it tells me to catch... If I try doing so, throw a Pokeball.. It escapes 80% of the time. Think I am better off doing Max Lair battles given there's a 100% capture chance over there, lol.