Tangentially related:

I can understand that CMU wouold hold copyright to most things, under
the work for hire doctrine.  But have their been code contributions from
members of the community?   I am unaware of any CLA (which is good -
they add friction and alienate some contributors), so I'd expect
inbound=outbound licensing, which would mean CMU is not in a position to
relicense.  But it of course depends on the details of those particular
files, which should be clear from VCS history.