my colubrids - 1 Corn, 2 Milk Snakes - are garbage disposals. they're just babies on fuzzies tho. did your Corn constrict as a baby? my Corn and Milks does not. thank goodness they eat f/t. i hope they start to constrict when they get to hoppers.
anyway did your 4 yr old Corn eventually eat the mouse after knocking it down and standing over it like a Cobra? i've had BP's who are picky eaters do this. they would defensively strike the rodent, instead of striking, coiling and eating.
when do u plan on feeding it again? i would chalk this up as a 1 time thing if all goes well next time or as a case of temps-season/brumation if behavior continues.
anyway i hope others peep in with their thoughts.