I may also simply be unaware of the possibly similar works on this problem too.
Recorded compatibalist conceptions of free will are several centuries older than academia, so I don't think it was ever really a publishable insight. (You got it on your own, I got it on my own, and so have a lot of people throughout history - it's just that not everyone agrees.)
I don't know about the second question...assuming the premise is true, I suppose either they did not try or it wasn't accepted, I'm not sufficiently knowledgeable about academic philosophy to speculate!
I feel that a lot of what's in LW (written by Eliezer or others) should be in mainstream academia. Not necessarily the most controversial views (the insistence on the MW hypothesis, cryonics, the FAI ...), but a lot of the work on overcoming biases should be there, be criticized there and be improved there.
For example, a few debiasing methods and a more formal explanation of LW's peculiar solution to free will (and more, these are only examples).
I don't really get why LW's content isn't in mainstream academia to be honest.
I get that peer review is not the best (far from it, although it's still the best we have, and post-publication peer-review is also improving, see PubPeer), that some would too readily dismiss LW's content, but not all. Lots would play by the rules and provide genuine criticisms during peer-review (which will lead to the alteration of the content of course), along with criticisms post publication. This is in my opinion something that has to happen.
LW, Eliezer, etc, can't stay on the "crank" level, not playing by the rules, publishing books and no papers. Blogs are indeed faster and reach a bigger amount of people, but I'm not arguing for only publishing in academia. Blogs can (and should) continue.
Tell me what you think, as I seem to have missed something with this topic.