The requirements for joining screen you are shown before you create your application wrote:
-Can stay active on the Forums, Teamspeak, and IN-Game
Everyone sees this before they enter any info for their application. If you can't do those three things and something happens to you because of such you shouldn't get some special treatment around the thing you missed. Upon joining he said he would actively check the forums, which he didn't do, and got demoted because of such (Technically he got demoted for not wearing his tags, but if he would've checked the forums he wouldn't have had a problem). Make him go through the recruit process again just like everyone else. The only exception would be if he was on LOA, which he wasn't.