Don't see much mention of fire risk from EPS beads in cavity walls.  Presumably because the risk is negligible.

But Dritherm 32 has zero fire risk. Is that sufficient reason to choose Dritherm over blown EPS beads? Given the often poor workmanship in installing Dritherm or similar?

If you have a fire that is affecting the cavity insulation you have much bigger issue than whether it is flammable in any way ... probably wouldn’t be much left of the timber parts of the structure of the building by that point.