I finally found the culprits behind the dForce mischief. It seems that not just some DAZ published environments came with their own animation keyframes (Looking at you Tesla3DCorp). No, also some older (2018 and older) products of "Sangriart" and "OutOfTouch" aren't playing nicely together with dForce. So I highly advise you to mix Sangriarts older models with care into your creations or be willing to readjust the bones, if they get messed up in the simulation. If I'm not mistaken, back then dForce wasn't part of the public DAZStudio, so stuff like this can happen.
So have fun with the keyframes I used for various simulations in the process. This series was mainly for the