What a pity
! Not that I really like the Green GT - on the pictures I saw it looks rather ugly - but I love the idea of allowing competitors to race new technologies outside the competition.
For privateers or small teams putting a hydrogen car on track is probably a little bit too ambitious - you need serious budget and engineering ressources. The labs of Toyota, Porsche, BMW, Mercedes and the like should be full of such stuff - I actually hope that more manufactorers will be going for a Garage 56 entry in the future.
I would expect this at least from the one which claims to have "Vorsprung durch Technik"....