Do you have another big screen Sega pin to cross examine with?

It's not identical, or remotely the same. These big screen Sega games generate their own high voltage within the display itself. The display receives 12v, 5v, and two grounds from the game via the 4 pin power connector. Power the game on with the display fully connected and check for these two voltages at the display's header pins that connect to the board. Also check for 5v at the display driver board that piggybacks on top of the display itself. If this board is not turning on, it will cause nothing to appear on the screen. Unfortunately there is no way to be absolutely sure the driver board is or is not the problem, but there's a good chance the panel itself has failed.

Have you considered SmartDMD? You can build a kit for half the price as a new DMD.

You must have a Vishay display, as these use 24v instead of 12v. Every brand has a different voltage for this input. Can you verify yours is a Dale/Vishay? Your 24v supply is too low. Do you see a 24v test point on your power supply board (the board in the upper left of the backbox)?

https://pinside.com/pinball/forum/topic/diy-addams-family-poor-mans-color-dmd

First of all thanks for your continued support for the DMD Extender, I
really appreciate it.

The only issue with my personal life is getting time to do things with the
DMD Extender - I have a full time job, a family, and other projects on the
go! It's hard to fit it all in. However, my wife is now helping with the
administration and emails so I'm getting a lot more time to do the
manufacture and testing of the kits that are getting ordered. I'm
continually overwhelmed by the popularity of this thing.