Problem began a little over a month ago, when it stopped making any/much ice. I ran diagnostics at that time, but we also coincidentally cleaned out the bottom freezer portion and the following day I had a full bucket of ice. At that point I figured the freezer just needed a chance to defrost.

In the last week, the freezer seems to be losing it's freeze on occasion (sometimes kid's ice pops are frozen, sometimes they're liquid). It was also doing this to a lesser degree a month ago when it stopped making ice. Now, in the last couple days the refrigerator is not maintaining temperature. Whereas last month I could put my hand through the door where ice is made and it was cold/frozen (even while not making much ice), now it is warm.

These seem to be the pertinent diagnostic codes:

Service Test-56: Ice Maker Error Codes
E5 = Ice maker thermistor is bad. Ice storage temperature satisfied but ice mold in frozen state too long. Possible ice mold thermistor issue.

Service Test-58: Ice Maker Heater Activation and Thermistor
00 = ice maker heater off; temperature warmer than harvest temperature

Guessing the thermistor seems to be the culprit, but wanted to verify I'm not missing anything or if any other steps should be taken.

Thanks in advance!