I do not mind time skip. Gilbert's objective is to get his book send out to be printed asap. He should have guest (a friend/bardic associate) who picks the book and delivers it to print. Anyways Gilbert does not reveal his tiefling status to Ehren but tells his deception is for his own (and other heirs) safety and leave it at that. Requesting Ehren does not mention Gilbert's exchistence to Crassus Antillus.