I haven't thought about this in quite a while, but here are a couple of points:
(1) We can most certainly compute ROHF-CCSD(T) energies. These are handled using semi-canonical ROHF orbitals, and all non-Brillouin terms are included, as they should be.
(2) A "conventional" open-shell B-CCD(T) calculation could start from either an ROHF or UHF reference, but it's not clear to me that the final orbitals would be different. That is, isn't a standard spin-orbital-basis B-CCD open-shell wave function uniquely defined? Furthermore, the resulting orbitals would be spin polarized, regardless of whether a proper ROHF determinant was used as the initial guess. (Note that difference would occur if core orbitals were frozen, however.)
(3) @loriab's question about the Python driver is very much worth investigating, as it may simply be a matter of making sure the semicanonicalization occurs for the B-CC cases. I'd be interested to see if my recollection that ROHF- and UHF-guess B-CC are the same (sans frozen core).
(4) Some years ago I published an alternative "RB-CCD(T)" method that maintains the spin-restricted nature of the Brueckner orbitals based on a symmetric spin-orbital formulation. I didn't carry this over to PSI4, but it wouldn't take too much effort to make it work, if there's interest.
(5) @loriab, the cctriples code is called from within ccenergy, I believe rather than by the Python driver.