Sasless - they were there because they had been called out and asked to be there - the fact that the MRT eventually walked them down is irrelevant. That they had comms with the MRT is completely normal and it isn't unusual to have to hand the job over to MRT if the weather precludes the helicopter rescue.
Just because the climbers were walked down by MRT doesn't mean they weren't lost, scared, hypothermic or mildly incapacitated - you are reading too much into the phrase 'walked down by MRT'.
Similarly, your analysis of the terrain from the comfort of your armchair bears no relation to what they were actually experiencing on the night - my last night job in the mountains sadly ended up as a body recovery of a person who had wandered only yards off a marked trail in cloud and failing light and ended up over a 400' drop.
The short answer to your question is - they were there because they were doing their job.