Well, this is how I solved it:
Maybe not as eloquent as many of you script gurus would have done it, but this works.
_this select 0
@ (alive player)
player addAction ["Set Rally Point","rp.sqs",false, -1, false, true, "false"];
@ (! alive player)
removeAction select 0;
And so the rp.sqs
player playMove "AinvPknlMstpSnonWnonDnon_medic_2";
"respawn_west" setMarkerPos position player;
flagpoint setPos getMarkerPos "respawn_west";
player sideChat "New Rallypoint established!"
So here it is and free to use for anyone who wants it.
ALL players get access to ALL extra actions used.
Edit: flagpoint is the name of my flagpole.