Looking at it from a rational perspective, Kerensky and Co. would have HAD to have men on the inside. Why?
Because the Prinz Eugen was taken intact. Boarding is a dicey situation when the enemy vessel isn't actively manuevering to avoid boarding attempts, much less actively manuevering AND firing weapons.
There's also the matter of the PE Jumping away from the formation-figure a 360 degree by 360 degree search area with a 30LY radius they could, theoretically, jump into, figure that the Staff of both sides are NOT blithering idiots. Without an inside man, the Fleet would have a very hard time locating the target flotilla to begin with, though it is interesting that the Eugen's officers didn't disperse their comrades across several points to make a rendezvous later-the first move one would logically take, breaking away from "Kerensky's Fleet", and a standard Naval evasion manuever when breaking from ANY Convoy.
An "Inside man" explains how Kerensky was able to find/round up that group as quickly as he did, and explains how a ship with that MUCH defensive firepower could be taken by Marines without mass casualties and/or destruction of the vessel's ability to...y'know, jump and carry stuff.