One of mine is a major introvert and socially a bit awkward and anxious so I get how hard it is to hear about this. But sometimes just having structure and something to do is better than sitting alone on a dorm room. A job may not result in good friends, but may get him out of his room and give him a few more people to say hi to. Some clubs are very loose and can be cliquey. Others very welcoming and open to all.
Is he a gamer or could he be? Many schools have gaming groups that play thongs like magic and often have kids that are not the typical cool kids. Of course that is not always true, but could be a start. The other advice I would give my kid is to look for the other kids that look lonely and try to connect with them.
At this point in time, having acquaintances is not bad. It takes a while to go beyond that to real friendship.
Hope things get better for him.