That is indeed an interesting matchup. Taz was capable of getting the Tazmission on bigger guys as evidenced by him locking it on Bam Bam. Now Bam Bam is by far and away a better wrestler than Fatu, but Taz lost to Bam Bam. Rikishi was pretty bad in the ring, but he had some stuff that could hurt Taz. That kick he would use and the piledriver would both stop Taz. The Tazmission is equally lethal though, so it could easily go either way.