Why didn't C!M apparate?

[macfotuk at yahoo.com]

No: HPFGUIDX 113631

Unless he was ordered to stay put at Hogwart's by LV*, why didn't C!
M apparate to join his master? How come he didn't 'know' from his 
left arm dark mark that LV had been re-embodied? he asks Harry 
several times if LV was really back.

* on a theme related to how is it that the triwizard cup was a both 
ways multiple journey portkey (thread a month or so back), WHY would 
C!M, having achieved his task of sending HP to LV, not 'get the heck 
out of there'. 

I know there's a theory that Harry is 'allowed' to escape (taking 
back misinformation), but if this is NOT the case then it seems LV 
is callously ordering C!M to stay put and sacrifice himself 
(possibly LV knows ESE!Fudge is on his way to sort it all out, i.e. 
silence Crouch Jr for ever more).

On that last theme, everyone asks how is it that Fudge got a 
deatheater there so fast - but could they not use either apparition 
or, if not closeby enough to central Hogwart's, a MoM approved 
portkey (DDs brings Harry direct to his office at the end of OotP). 
Certainly, the DE's show up at Little Whingeing out of thin air in 
Ch1 OotP and so can either apparate or were sent by an unregistered 
ministry portkey.