How do I deauthorize Adobe Digital Editions on an unresponsive device (tablet)?

Can someone at Adobe please either de-authorize one specific device (Aldiko ereader freeware on LePan II Android tablet) or simply de-authorize all of them so that I can re-authorize the ones I'm actually using?

Background: I've been using Sony eReader/AdobeDRM/Kobo since 2006. I'm planning on replacing my 2012 Android tablet running Aldiko e-book reader (freeware). It doesn't give me an option to deauthorize my Adobe DRM content (it used to, but it would crash instead of deauthorizing, now it just fails to give me a Deauthorize option). So I have at least 4 items already authorized and possibly more, and my replacement tablet makes one more. It's very possible after 10 years that I already have all 6 authorizations used up. I tried to contact Adobe Chat (case # 0222697383) and was told to come here. But on this site, threads such as https://forums.adobe.com/thread/2277128 and several others make it look like no one from Adobe is reading these, though the agent I chatted with after being pressed repeatedly claimed that Adobe employees do read this and act upon the requests. If you ARE an Adobe employee reading this, I would encourage you to resolve my and all these other threads out there with frustrated customers getting the runaround. As for myself, I would much rather get this resolved BEFORE laying out the money for a new tablet or ereader.