I think if in "The Squire of Gothos" Trelaine was not limited to looking at only Earth, it could account for the other "out of time" items like Napoleon and certainly the Salt Creature (even if it had been "extinct" for an unknown number of years). Jaeger wasn't too specific other than "notice the period" and if he was just looking at the architecture it'd start at the 12th century.
All the other more recent stuff, like Napoleon, Salt Creature, etc could be from viewing closer colonies and alien planets or he was just playing with Kirk about the extent of his actual power to observe great distances. Trelaine could've even pulled that information directly from the Enterprise's computers.
Just a thought anyway.