Why didn't I think of the delta commands... (not tested)
Function PointingAtEntity(SourceID,TargetID)
If Abs(DeltaYaw(SourceID,TargetID))<0.00001
If Abs(DeltaPitch(SourceID,TargetID))<0.00001 Then Return True
EndIf
End Function
The delta commands don't seem to return 0, but this will do :)