One question. Who are you to judge whether he is a muslim or not? From what I know, Islam is not a commit one sin and you are going to hell type religion. There is a balance. A man may not pray but may be better than that. He could be one who brings peace and prosperity. Are you saying that this man is not a muslim just because he doesn't pray?
It is a pleasure to stand upon the shore, and to see ships tost upon the sea: a pleasure to stand in the window of a castle, and to see a battle and the adventures thereof below: but no pleasure is comparable to standing upon the vantage ground of truth . . . and to see the errors, and wanderings, and mists, and tempests, in the vale below.