Am in complete agreement with you on this: Trotter is certainly one of the world's foremost Messiaen interpreters for organ. Dame Gillian, to my taste, does not quite manage to make as much of the music, and sounds almost rushed by comparison (particularly in that exquisite Communion movement).
I find it hard to believe that Trotter is not himself a fan of Messiaen, though, having recorded the disc in question, Les Corps glorieux (I forget where) and programming his music fairly regularly in recitals. Having said that, I don't know how willing he would be to do a complete Messiaen recording, which I would love!