Can bacterial RNA be degraded at -80⁰C in a SDS solution?
I think it is relatively unlikely that the RNA will degrade under these conditions. For the future, I would handle this differently:


You can centrifuge the cells and snap freeze them in an appropriate
buffer in liquid nitrogen and then store them at -80°C. I would not freeze the dry pellet, as these are often hard to re-dissolve after freezing.
Alternatively, you centrifuge them, break them up with Trizol (or whatever you use for this purpose) and freeze them in this solution. This will be
safer as it completely denatures all proteins including all nucleases.


I would choose (and have done this already several times with cell samples that I couldn't process without problems) the second method.