The Gambinos has an alliance with the Aryan Brotherhood and the other families,if the made men are old and went to to a prison outsite the east coast for sure have a deal with the most powerful gangs in the prison and pay for protection.

In the mafia prince book Leonetti that payed two mexicans for be his uncle's bodyguards,scarfo calls him my 2 pistoleros and belong to the mexican mafia.

This is an example,the mafiosi are tought guys and in prison this is enought to take the respect of the normal prisoner for the gang members must pay for avoid problems and don't make the end of Pete Scibetta.