How to further troubleshoot a refrigerator freezer not working.

I have a 14yr old freezer on bottom Amana fridge that suddenly stopped working. Both the freezer and fridge section are 61 degrees. The ambient air temp is 70 so it is a "little cool" but nothing stays frozen. It stopped working 2 days ago and now everything is melted.

Opening the back I see the fan running and their is airflow to the fridge area. With a voltmeter I was reading 119v AC going to start relay when the relay was unplugged and leads in pins that connect to it. When connected, all of the fans are running and I do hear a hum and vibration from the condenser and the voltage detector detects voltage to starter relay.So I assume that the condenser is getting power and running.

When remove the start relay does not have "broken / loose metal sounds" when shaken

With power off the three pins on compressor read 5.2, 4.2 and 8.8 ohms. It is open between all pins and copper tubing. Between copper tubing and where green wire goes reads < 1ohm. This tells me the compressor is likely electrically sound.

I vacuumed off the coils below fridge then used a leaf blower to blow remaining from coils. They are clear and free. The freezer and fridge were evacuated of all items and are bare as we needed our perishables moved to another fridge.

Touching coils below fridge from back area near compressor and from front below door are both very slightly warm and the coils within the fridge behind panel in freezer area are room temperature. The coils in freezer are are from my understanding supposed to be extremely cold often with presence of ice on them. Instead they are room temperature.

I do not hear clicking from start relay indicating an overload and safety shutoff.

I suspect low coolant or that the condenser is running with too low pressure in a barely working capacity.

This is reaching my DIY capability level and I want to know if anyone has any suggestions before I buy another fridge.