This is just a query. I've found a Thomas Bosc playing rugby union for Perpignan.
This was on the same day, albeit six hours before, a Catalans v Hull KR match in the same city. Bosc played just nine minutes for USAP and didn't ever play again. There's no record of a date of birth for him on the rugby union records either.
Does anyone remember if this was "our" Thomas Bosc that came on for USAP in some kind of publicity thing? It seems extremely unlikely but very coincidental none the same.