Currently, my server hosting kitten1 and kitten2 (tor guard and fallback directory) is under seizure since 14/05 11h. Private key are under encrypted volume and may be protected, but please revoke immediatly kitten1 & kitten2 tor node. Those nodes are also fallback directory.
I don't know any context or background but if you fear this could happen to you again, I recommend to use tor's OfflineMasterKey feature (without copying the master key to the server) with a short keylifetime (i.e. 7 days), especially if it is a fallback dir (which requires a tor source code change to remove it).
Could you also confirm the relay fingerprints (in addition to the nicknames)?
thanks, nusenu