Oh my, you have the highly coveted Optrex DMF 50202NY-LY and you haven't transplanted it into the QY100 yet?? How is this possible, what are you waiting for?!?!?? LOL
Have you looked inside the TG300 yet?? Do you have any pics??? If you're comfortable taking things apart, there is a good chance that removing the display from the TG300 wouldn't be destructive.? You may be able to temporarily "loan" it to the QY100 by simply unplugging it and removing the 4 screws holding it in place.?? If it's like the QY100, it probably has an 8 wire harness for the display that plugs into the main board.?? According to the datasheet there should be another 2 wire harness for the LED backlight.? I would guess that the display itself should have the same physical dimensions and the same electrical characteristics as the DMF 50202N.? My assumption would be that the display would work in the QY100 just by plugging it in, assuming the connector is the same, but you should compare the datasheets to be sure.? The real trick is powering the LED backlight.? If you could measure how the TG300 powers that, then you're getting very close. ?
Looking at the datasheet, I'm not clear on what the LED backlight needs for power.? There is something about 16V reverse voltage and 7.6 - 8.8V forward voltage on page 7 of the datasheet, but I really have no idea what this means.
Depending on what the power requirements are, you might be able to find somewhere in the QY100 to get this power.? This seems to be the main challenge.