Fade/Dead screen on Keitai

Just recently got a Keitai tamagotchi in the mail and while the shell and tag are in super nice condition the screen is too faded to even make out. I opened it up cleaned the board with alcohol and it seems to have only gotten worse. Is there anything I can do to save it short of moving an entirely different set of innards over to it?

(It's one of the white with black buttons ones that has the P1 background and I'd really hate to just chuck it when the shell is in such nice condition)

This is such a weird follow-up that I never would have expected to make but it's working suddenly and I have no idea why.

After basically giving up on it last night I blew into the battery tab slot and it made the screen slightly more visible but still not usable. Eventually though the condensation from my breath broke the contact between the battery and the pet and it would not recognize batteries anymore. At that point I completely wrote it off for the night. This morning however I got curious and put a battery in and suddenly it works fine. Anyone know what the hell happened with that?