I’ve looked at this before and I think any idea of using DPF for breeding fission fuel is a red herring. First, our theory says that performance will be orders of magnitude better with pB11 than with D or DT, so conversely yield is way down with any fuel producing neutrons. You would need a huge re-design from a pB11 generator and you would run into all the damage done by the neutrons. So I don’t think it would work.
Conversely, once you have operating pB11 generators, fission energy is obsolete, so uranium could be locked up and fission phased out everywhere.