so before you had the index.php from the portal and manually added the code for the arcade to it, and it was working ?
Maybe check your PlugIn "ibProArcade: Integration in index.php" if this has actual content.
If not, I really have to investigate as I can't find any place in the code where the problem is not solved
If you want, you can provide AdminCP+FTP access via PM and I will try a direct search&fix