There’s too much RF by the PSU. Meanwell PSUs have a decent reputation and allegedly pass EMC testing. The 857 should work fine in high RF environments, I’d blame the PSU first.
For 2m, I’m not surprised you have problems with the antenna that close. For a PSU that passes EMC tests, I’d expect radiated fields picked up on the mains cable, or radiated fields picked up by the house wiring and conducted up the mains cable to the PSU to be handled by the mains fitering (typically built in the mains connector on the case.) So it’s either direct pickup through the case or pickup on the DC power cable and getting back into the PSU.
For HF and an EFHW, I’d guess there is significant RF on your coax that is radiating into the shack.
It suggests the filtering on the output of the PSU is poor or missing or being overloaded and your choke is not in the right place or right type. Dressing the cables and positioning the choke as close to the PSU should help.
It’s 22 years since I did EMC testing on medical devices as part of my job and I hated it then and hate EMC now. But a 10W erp interference level should be fixable easily.