So this might be common knowledge by now but in case anyone was like me running meta Azumarill strats with 3 others and STILL getting trashed...
Just solo the raid instead. SV's online services are ridiculously bad. You miss turns, hp bars glitch, endless lag etc. You aren't losing because Charizard is hard, you're losing because online raids don't work right.
But solo? The game is way more responsive. I used a Fake Tears Flutter Mane with 3 physical attacking AI partners and still won. After the first Overheat the AI doesn't reset its stats again (I think) so Fake Tears / Screech seem really powerful.