Chosen Solution
Ran Apple diagnostics code came back VDH002 which means could be problem with a storage device
The flashing question mark means that the drive is not being detected by the computer so yes, there is probably a drive problem. But I am probably wrong.
This is almost definitely due to a failing HDD cable. The 2012 13” MBP is known to have a design issue that causes the bottom plate to rub up against the HDD cable and wear it down over time. I would suggest removing the bottom plate and looking for signs of scuffing on the HDD cable where it routes over the optical drive. If you see any scuffing there you can be pretty confident the issue is due to a failing HDD cable. Check out this guide. It would also be smart to cover the area that is prone to scuffing with electrical or anti-static tape to prevent future scuffing of the cable.
