It's not the armor style I have issue with. Or that Ruby Weapon could be piloted in general. It's that so far, the Garleans are not the kinds of people to bring in non-Garleans into their experiments. See both the experiments in Castrum Abania and the weapon Estinean faced down for examples.

We also know that Gaius is the one who is spearheading the movement to take Ruby Weapon down and we see both Auri in the trailer talking with Gaius which suggests they are working with him. So I have a hard time seeing either of them piloting the very weapon that we are supposed to be destroying.

The armor of the pilot is also a completely different armor set then the armor of the Auri. The pilot has the Late Allagan meele armor set. The armor of the Auri is the Late Allagan casting set.