I think that makes good sense!As long as you know that there is some doubt then I don't see any problem. It can easily be changed if new evidence comes to light.
Apologies if I'm going over old ground.
Taking the relationship - cousin - between the other Giuseppe and Nicola listed on the 1911 census at face value then it would imply that Gaetano & Felice had at least one other brother. Assuming that Nicola is Gaetano's son.
Also on the 1911 census there is a Peter Jommi. He could also be Gaetano's son as there is a possible birth listed for him.
Did he take his middle name and change it to Peter?Yes, that's right.
The Peter on the 1911 census if he's who I think he is was listed as Vincenzo Pietro Donato on his birth record. There was an elder brother also called Pietro who died young.