I'm not sure if my character can actually help you and make the connections you are looking for but perhaps I can help give you ideas so that you and another can develop ways that would help your shy guy.
What are potential ways to get him out and about? If your character actively avoids large groups or groups of people in general, what are situations that you think will help him? Is he likely to go to those events if he develops a friendship with someone more out-going/willing to go there? Will he potentially act as a friend to keep someone company at one? Would it be possible to get him out if he thinks he needs to protect someone?
What are potential ways to get him out and about? If your character actively avoids large groups or groups of people in general, what are situations that you think will help him? Is he likely to go to those events if he develops a friendship with someone more out-going/willing to go there? Will he potentially act as a friend to keep someone company at one? Would it be possible to get him out if he thinks he needs to protect someone?