or you can network the .colormap field and compare that to player_localentnum in your csqc (which is one way to deal with splitscreen properly).
alternatively use writebytes. DP has no proper svc so you'll need to either hack tempentities to parse it, or to send it via stuffcmds. both of which can be sent using reliables without needing to depend on SendEntity callbacks at some vaguely defined later time.
and do you really have 256 player-specific stats?

why can you not compress them a little?