Capillary tube replacement. My wife had a service technician come in to her store to repair a true

Question

My wife had a service technician come in to her store to repair a true TSSU-60-16 salad unit.He found a leak, repaired it & recharged it with 134A refrigerant.He also informed her the capillary tube was plugged & needs to be replaced.1. According to the website this unit is supposed to use 404A refrigerant, will the 134A harm it? 2. He said it will be $500.00 to replace the capillary tube, is this reasonable? 3. Will the compressor fail sooner due to the plugged capillary tube? It seams to be working O.K. since his repair. Thanks, pressman