thats really bad advice depending on options the OP might have. telling people not to organize with people you disagree with is really shitty. If you're serious enough that you're joining a party you HAVE to realise you're going to be working with people who disagree with you on things. you have to find common ground and make your opinion known. its so much easier to get people to agree with you in person as opposed to online if you approach them non-combatively.

obviously none of this applies if the group is just straight up racist or homophobic, but just being "class reductionist" shouldnt be a deal breaker for anyone. educate yourself, educate others. that's literally one of the biggest goals of organizing anything right now, so if you're not willing to put that effort in you might as well just stay online.

op is being handed an opportunity to correct shitty ideas by being asked to give a talk. that's a good sign. i really hope they go for it instead of jumping ship