A followup after merging https://git.card10.badge.events.ccc.de/card10/firmware/-/merge_requests/399:
This directs all calls from the BTLE stacks internal BbBleDrvRand to our __wrap_BbBleDrvRand() which forwards it to epic_csprng_read()
BbBleDrvRand
__wrap_BbBleDrvRand()
epic_csprng_read()