Torque Arm Compliance Question

My truck is in the shop for repairs and I noticed a bad bushing in the torque arm mounted above the rear axle. The driver's side bushing is clearly ripped and in pretty bad shape. Upon taking my truck to the shop to have all repairs done, I was told that the torque arm did not need to be replaced any time soon.

"CUSTOMER REQUESTS QUOTE ON TORQUE ARM REPLACEMENT
DUE TO BUSHING DRY ROT.
INSPECTED TORQUE ARM AND DON'T THINK IT IS NECESSARY TO REPLACE ANY
TIME SOON."

My questions are as follows.

1. Is this a DOT Violation? All signs point to yes, per 49CFR393.207.
2. If it is indeed a DOT Violation, and this part is not replaced, and I have it in writing that I pointed out the defect and the tech advised against the repair at this time, am I legally covered?
3. If this is not a DOT Violation and appears to be holding despite a failing bushing, should I just let it ride and keep an eye on it?

I, myself just want to fix it and be on my way. If baffles me that a truck shop would be so quick to turn away easy money. Thanks in advance for your help!