You're looking for an unusual routing on exact dates in premium cabins one month prior to departure over the holidays? For this year?
Routing should be valid theoretically. Open jaw awards are permitted, as is one stopover. KE flies a 737 into REP, so that might be tough to get an award seat on.
Can't use SQ into REP, though, as SilkAir not SQ operates the SIN-REP route.