They don’t have to arrest everybody associated with him, only a few. Like the IRS broadcasts arresting a few alleged tax thiefs every year around tax return time to scare everyone into not cheating on their taxes. Same with this, that’s all they would do - and probably all they would need to do.
But how? Congress has no arrest powers. It would require a Congressional committee to send a criminal referral to DOJ first, citing the underlying criminal predicate. Congress can shout “arrest” all it wants, but it would be like a dog with its tongue cut out.