No, the safety is 100% the right call.
If you punt it, you can fair catch it, and set up the hail mary and/or be in a position where a penalty gets a tying FG.
A scramble and run, you give the ball back in FG position if any time left or something goes wrong.
A Safety, KU gets to run most of the time off (should've been all since the clock stops when it hits OOB, see Texas) and then you get to squib it to burn off the last ticks.
Great win guys! Glad to take my 100 in GTS!