The enmity between the pair boiled over in 2009 when they had a heated ringside row over McCrystal's refereeing of a fight between Oscar Siale and Wayne Orbell.
While McCrystal would love to see Welliver handed a date with Williams, his assertion the NZPBA "won't wear me" appears to be correct.
"They'll never let Sonny Bill fight against any of my top guys," he said.
Revill said he had no problems with Welliver, who he described as a "true boxer", however McCrystal's desire to see a unification bout was a case of someone wanting to "jump in on the act".
"Gary McCrystal and Chauncy Welliver want to jump on the bandwagon because Sonny is a star and they want to be part of that," Revill said. "When you get a spectacular fighter come on the scene everyone wants to jump on the bandwagon to make money out of him."
About the only thing the two seem to agree on is that Williams' manager Khoder Nasser will dictate the next move. NZPBA rules mean Williams must face a fighter rated in the organisation's top 10 in his first defence, while any second defence must be against the number one contender. Williams' next opponent will be carefully chosen by Nasser.
"You can understand where Khoder Nasser is coming from," Revill said. "He is on a money machine, he is on a gravy train so why not ride it?
"Whatever he does is good for New Zealand boxing. That's the part that I'm getting out of it. People wouldn't see the likes of [undercard fighter] David Aloua. Now they are live on TV. That exposure is good for them and good for the sport. Having a name like Sonny Bill Williams, who is a household name and is marketable, as long as he stays champion it is going to do our sport good."
McCrystal couldn't agree less.
"Khoder would never let Sonny Bill in with Chauncy Welliver, he'd never put him in with Shane Cameron.
"They won't be risking him at this stage, if ever."
* Revill, the referee of Wednesday night's fight, has defended the stoppage with just six seconds remaining in the first round.
"The reason I stopped the fight is because [Tillman's] head actually left the ropes, it went out of the ropes and he was looking away from Sonny Bill. He had no protection at all. Had he gone down and not woken up it would be on my conscience the rest of my life." Revill said he spoke to Tillman two minutes after the fight and he was still nonsensical.
"He didn't even know what had happened."