Out of curiosity, am I the only one who's really struggling to get into non-7 star raids in last month or so? Almost always the game fails to connect, I think I manage to get into 1 out of 10 when i'm lucky and often have to go through 3-4 refreshes before one lets me in.
(Doesn't help that most of the people I find are bringing level 60-70 mons to 6 stars...)
Not sure if it helps, but I haven't had any problems connecting (finding players that know what they're doing on the other hand). If you haven't caught the Decidueye yet, there's a few videos on how you can solo it (though may take a few tries). Manage to solo it with a Ceruledge.