Is this a Maytag MFI2067AES control board issue?

[DMK]

I read through this topic and there was no resolution from the poster.  https://appliantology.org/topic/67175-whirlpool-refrigerator-model-gx2fhdxvq07-ice-build-up-behind-rear-wall/

I have the same problem (ice buildup only on the top of the evaporator) so am wondering if I should replace the control board as BrntToast suggests.  An appliance repair technician said it was a clog in the sealed system but that didn't sit well with me.  So I kept digging...

Here's a picture of the ice buildup before I defrosted it the first time.  I've done it once since about a week later and it looked basically the same.  https://imgur.com/a/sW6zGHp

The refrigerator portion stays around 50^o while the freezer keeps things frozen and makes ice - albeit not as fast as it should.  Thanks in advance for any assistance!