Very very similar happened to one of our P2’s on a Longhaul Fleet in the cruise a few years back (I suspect there will be a record in the bulletins somewhere but can’t find it ATM).. Just as in the Flybe case the captain had a hard time countering some of the rudder inputs and it took a lot of effort by all involved to obtain a safe outcome.
Sadly the copilot who suffered the seizure in that event never got his licence back.