For Sevenoaks, the 24-16 result was their third win on the bounce.
A Ciaran Mcgann penalty opened the scoring, before Oaks hit back with a try from scrum half Ethan Jones who jinked through the Guernsey defence from 30 metres out.
That was converted by Ben Adams, who then added a penalty for the home side.
Raiders were quickly back in touch when hooker Phil Le Noury struck from close range.
The sides exchanged penalties to go in with Sevenoaks leading 13-11.
Oaks stretched their lead after the break through two more penalties from Adams, before Raiders exerted the pressure in the last quarter.
Anthony Armstrong scored a try on 71 minutes, but the conversion was missed.
There was a flurry of yellow cards before Sevenoaks sealed the game with just four minutes to go after breaking out from defence and driving over from a lineout. Scott Sedgwick dotted the ball down.
Raiders finish this year with another trip, this time to Westcombe Park, who sit five points below them and racked up a big win 68-19 against Worthing on Saturday.
