Hi Gerry - just watched your Video - thumbs up

Resistors especially the precision SMD ones can easily damaged ore pre-damaged by only handling the PCB.
This can happen during the manufacturing process and pass all the test and calibration processes.
I know this, because we faced the same problem in our our factory while handling a very big Power supply with some precision resistors populated.
The PSU's where tested and shipped out without any problem and after some days / weeks of operation together with vibrations from the end application the PSU failed.
After very deeply investigation's and verification's we found that those resistors tends to have micro cracks and we changed the handling in our process to avoid any stress to the PCB.
After that the problem solved.
In your case this can also be explained by a single component failure, but as an conclusion for me (and a recommendation for everyone) I try to avoid any stress or bending while handling any PCB.
Rgds Arne