if an SE cable is identified as flame retardant covering per sec #338.2 , what is a actul fire rating of the cable ? can it penetrate a (1) hour tenent seperation without any additional covering or sleeving to maintain the fire resistance rating ?

It depends on what type of system you will
use to seal that wall, you need to check the manufacture specs, and it will tell you
how to seal that wall to maintain the 1 hour rating.