106 ID is still fighting at what the Germans needed as their main supply route on 21 December, Now they are surrounded, deprived of their artillery ( most of it) and support echelons- which are the guys that bug out, small hint, mobile bath unit vs panzer spearhead bath unit is supposed to run away. But they only surrender after the failure of relieving forces. - Hint AFTER.
The bags of prisoners at Kasserine are around 3,000 ( compared to the 600k Axis prisoners in Tunis and say 49,000 at Alamein) and thats after Fedendall had refused them permission to retreat when they could have.
The panic in the US forces mainly exists in the head of Bradley, maybe Eisenhower briefly, and the press corps every other senior commander on the allied side, well captain on up really is marching to the sound of the guns or alerting major formations for movement. McAuliffe knows this, if McAuliffe turns into a gibbering idiot, the guy who replaces him will know that ( Radios are a thing) and after all the Brits held Oosterbeek for a week so 3-4 days is not really a problem.
The totally ridiculous proposition is that a guy who jumped into Normandy with a carbine and landed at Market Garden after a 25 year career in the army is going to turn into a coward, ignore his orders and run away, when he has a full infantry division( with extra automatic weapons and bazookas) an outsized ammo supply of APDS ammunition for their organic AT guns, elements of an armoured div combat command, an ad hoc battlegroup based on elements of a second Combat Command and a veteran infantry division, 2 armoured field artillery regiments, two corps level artillery regiments, a tank destroyer battalion, His own air recon unit and two combat engineer battalions dug in around defensible position surrounded by a single infantry regiment, later supported by a second infantry regiment and some very badly handled armour because its cold.
He could probably have defeated ( as in buttfucked defeated) a full Panzercorps attacking him and he knows it.