OK, so I have another theory that condenses and takes off of the other theory. I still think that Damon will want Ric to not uncompel Elena, but I don't think that will last long now. I'm thinking that the point of Elena losing her memories of loving Damon will hopefully only be for a few episodes for a couple of reasons:
1.) To get Liam into Elena and the group's life because he probably does have a hidden agenda and is likely related somehow/someway to Kai. I mean, as florencia7 and others pointed out, how did he know that Elena likes bad boys? I mean, there's no way anyone who *did* know Elena even remotely well (or had even asked about her) didn't know that she was majorly, majorly, MAJORLY into her last boyfriend who DIED up until like two seconds ago and so to make the moves on her like that? Yeah, something fishy going on there.
2.) When Damon and Bonnie returns,* I'm thinking he'll see Elena with Liam looking happy, she'll see Damon and be/say horrible things to him, maybe not realize that Bonnie is back and wish he was dead, blah, blah, blah. Damon being Damon will take it as proof that deep down she still feels these things about him, blah, blah, blah because of his terrible self-esteem and issues. Therefore he will be convinced that, yes, he is the worst for her because of this and because the two of them never had that whole toxicity talk. So he'll want Ric to not uncompel her.
* I'm still thinking that they return within the 4-6 episode range. And hey, majorly mini spoiler alert! The next episode title is:
[Spoiler (click to open)]"Black Hole Sun" and that = hello, SOLAR ECLIPSE! So I'm thinking that the next episode is definitely possible for our new besties to make their grand return.
3.) Either Damon will tell Bonnie to tell Ric to not uncompel Elena because he wants her to be happy (blah, blah, blah) and take off to join Stefan in Savannah thus not telling Ric himself because Damon is nothing if not one who chooses to make his own life a living hell and denying himself the joy of even seeing his best friend is so him. Plus, yes, he does have to go see Stefan. Or, he tells Ric and Ric semi-agrees first but plans on changing his mind, then Damon takes off so Ric doesn't have the chance to change his mind. Either way, Ric winds up saying 'fuck this shit' because he knows Damon is being an idiot and he uncompels Elena on his own because he's going to do what *actually* makes Elena happy.
4.) When Damon and Bonnie return, things have changed with who they are. Bonnie will no longer be the anchor, she will be alive and have her magic. And Damon? I still say it's quite possible that Damon will be human. In 1994, he was a vampire, but in 2014, he may not. Remember Tyler didn't realize he was human until Caroline hugged him so hard and then he cut himself and didn't heal. And Damon had to check to see if he had fangs first. So Damon probably won't check to see if he's a vampire when he gets back to 2014, just assuming that he is. I say he will be human/Traveler, and that will come into play *after* Elena shows up wherever Damon is after Ric has uncompeled her. She plans on kicking his ass for not wanting her uncompelled, but they wind up just falling into each others arms, because, duh, they're Damon and Elena... but then, I dunno, Stefan gets kidnapped by Tripp or something, LOL!
5.) Still, because Damon wanted her not uncompelled, ALL of the Scooby Gang--including Elena--will know:
(a) How much Damon loves her, and puts her happiness first.
(b) The others will realize--thanks in part to what Bonnie has learned about him and how he feels how others see him--that Damon believes they all essentially still hate him, see him as a monster and wish he was gone.
(c) Elena will truly realize just how deeply his issues are ingrained.
6.) So we *will* get the Damon thinks he's a monster issues dealt with, the toxicity issues dealt with, the others finally getting that Damon is not the EVUL and Damon realizing that the others don't think he's the EVUL AND if Damon is human, Julie/Caroline D. get to write the Elena-vampire/Damon-human story they wanted to write with Damon getting the cure after season 04.