How to Request for Help with Overvolted WD Reds

I’m reaching out to request help and guidance regarding an issue I’m experiencing with a set of WD Red hard drives that appear to have been overvolted. These drives were originally part of a NAS setup and functioned reliably until a recent hardware upgrade, after which they were inadvertently subjected to a higher-than-specified voltage from the power supply unit.

Specifically, the drives in question are multiple WD Red 4TB (WD40EFRX) units, designed for 5V/12V input. Due to a misconfiguration in the power delivery, they were briefly exposed to a voltage above the 12V threshold—likely in the 14–15V range—before the issue was detected and corrected. Since then, none of the affected drives spin up or show any signs of activity when connected to power, either directly or through a SATA docking station. I've already confirmed the SATA power connectors are delivering correct voltage now, so the issue seems isolated to damage caused during the overvoltage event.

I suspect that the damage might be limited to the TVS diodes or PCB components that protect against overvoltage. I’ve inspected the PCBs, and although I do not see any obvious scorching or blown components, I understand that TVS diodes can silently fail by shorting, thereby preventing the drive from powering up. However, I do not want to attempt DIY repairs—such as removing the TVS diode—without expert input, as I risk further damage or data loss.

The data on these drives is extremely valuable, and my primary goal is safe data recovery. I would appreciate any advice or recommended steps from individuals or professionals who have dealt with similar issues. Specifically, I’m seeking:

Confirmation whether this is likely a PCB issue

Safe troubleshooting techniques

Recommendations for data recovery specialists experienced with WD Reds and overvoltage scenarios

Availability of compatible donor PCBs if needed

If anyone has experience recovering data from overvolted WD Reds, or if there's a known standard procedure to test or repair this kind of issue without risking the platters, please let me know. I’d be grateful for any help, whether it’s technical advice, resources, or references to trusted recovery services. Thank you in advance.