"I've seen the YouTube clips of Cameron sparring Vaitele, he got dropped with 18oz gloves on," McCracken said.
"I went 12 rounds with Shane and he couldn't hurt me, so really what does Soi think he's going to be able to do - I'll break him down just like I did to Aloua."
Soi, 27, who is based in Samoa but does his training camps in Auckland under veteran trainer Lolo Heimuli, vowed revenge on Aloua's behalf.
"I am looking forward to claiming back the titles for New Zealand and Samoa, and to overcoming the man who beat my friend," Soi said.
Former world champion Danny Green, who has sparred numerous times with McCracken and commentated at November's Super 8 event, predicted a tough fight.
"Vaitele Soi's got more skill ... he's got a great chin, he's got a couple of detonators in each hand, so it's going to be an incredible fight," Green said.
Next month's Super 8 fight card includes another eight-man cruiserweight knockout event, with Israel Adesanya, Lance Bryant, Monty Filimaea and Australian Daniel Ammann confirmed.
Blogger Cameron Slater will face cricketer Jesse Ryder in a celebrity bout.