Have you tried a Plugin Rescan in Ableton? If you hold ALT while clicking Rescan Ableton will disregard previous plugin status, I think…
edit… Found a support document:
In the Plug-Ins tab, you’ll notice a button that says Rescan. Just clicking that will not rescan Blacklisted plug-ins.To reset the blacklist, hold down the Option/Alt key on your keyboard, then click Rescan while continuing to hold down Option/Alt. Ableton will begin to reset and rescan all of your plug-ins.
…so hopefully that will work