Interesting quote from Meisha Merlin website on the US edition of Traitor's Knot..
"Davien the Betrayer, an enigmatic recluse, and a peril in his own right"
Another interpretation of Peril's Gate - the entrace to Kewar is the entrance to Davien's domain, ergo "A Gate into Peril..."
Maybe it reflects the "peril" of the unknown? All the townies know is that Davien started the rebellion that led to their ascendence. But did he do it for their benefit? Notice the terror they experienced at the stairway into Kewar in PG.
All the clansfolk know is that Davien's incited the rebellion which left them in nasty straits. Davien was also the one who lured Kamridian s'Ffalenn into Kewar, where he died horribly. They also have a terror of the unknown, because for all they know, he's out to kill them, too.
Davien is closemouthed about his ultimate aims, as well as why he took the actions he did in the past. He is not one to trifle with, because he obviously has, and is not afraid to use his power, to defend or destroy - at least, that is how it appears.
So I guess, yes, Davien is a "Peril." No one knows what motivates him or why. Many people equate "unknown" with "dangerous." Handle with caution until you are certain.