If you can be part of the social group without having to jump through hoops and showing that you don't "need" to be part of their clique. I figured that out in 5th grade when my
social circle wanted to kick my ass that friends can turn into your worst enemies. Maybe you didn't do anything, but all it takes is a believable rumor.
I became friends with specific people and eventually got to know everyone over time. Would tell different stories, supposedly "private", but it was to test them to see who was going to not be able to keep a secret. Most of the time it was made up, but it was never the same...that can get really hard to track. I usually expected someone to be resistant, but just by getting what they're about, getting them to open up and a good or bad vibe, I could work with it.
It's no different than when you're dating a gf and someone in her group doesn't particularly care for you. She's not going to say anything to your face about how she really feels, and she's going to tell her friend if she doesn't like it, tough.
I think you should get along with his friends, but being a suck up is flat out Beta, and for people starting out in a career, that, once they've proven their worth, can stop.
It's good to be part of different social circles esp. after high school. You have them all together at a party, interesting things happen (usually good because they're all from different areas).
They're going to be skeptical of you, don't worry about them, and over time you'll have a better idea on how the
social circle is.