It’s been made pretty clear - you might get away with one but you won’t get away with 2.
Sensible (but expensive, which is not an excuse) approach is to swap the fenns out for something approved.
Getting caught falling foul of this sort of thing is very bad for everyone - be careful because you don’t want to be the one setting the precedent. If you catch a stoat in a fenn trap, there is no excuse - you are illegal, the fact it happens is all the proof that is required.