Olivier Lemercier was invited to brief Harvard's ReichLab last week concerning the status of the Bell Beaker phenomenon. The slides and speak can be found [here].
Hopefully, this should be taken as an indication that the genetics community is starting to get moving on several Beaker individuals.
Lemercier has proposed the "Greek Implantation Model", which should not be construed as a place of origin, but rather a type of settlement activity. It's possible to reconcile the GIM with any of the origin theories.
I hope the Reich team is looking to Atlantic Europe with a level of effort comparable to its recent study on steppe population movements.