First set up a cold storage (with properly checking the new seed and addresses, with proper backups of the seed) and transfer your funds there.
And obviously also reset the HW (enter wrong PIN 3 times). Maybe even reinitialize it for an empty wallet and reinstall at least the bitcoin app.

Then even if they insist in recovering your seed, the most they can get is an old transaction history, if anything.
And yes, then I would not be scared to send it to them for fixing it.