User blog comment:Palantian/Saber/Arturia Pendragon vs. Pearl vs. Weiss Schnee/@comment-3343773-20160122034320/@comment-26051344-20160122035725

Look Shawn  admin Shadow7615 said that there are already three other existing battles:

1) Pearl vs Saber

2) Pearl vs Weiss

3) Saber vs Weiss

All three depict all three fighter being pit against one another, so to the wiki admins and other managers, they probably must fee that having a three way battle between the three all together, would be redundent or pointless as that would be repeating fights over and over.