Water damaged chromebook

[SpaceSage]

Hi guys, got a Lenovo 300e Chromebook 2nd Gen and it has a glass touchscreen, one of our (school) kids has managed to get water on it. I've salvaged the screen itself to replace another device that's got a smashed screen but when booted up there's blotches on the screen that looks like water but it's been drying for 2 days straight and I've tried leaving it on playing a video as well as used a low level heat gun to see if it's moisture trapped but nothing seems to work, any ideas?

Much appreciated.

[synaesthesia]

Once it's in the panel it's not coming out - if it ever did (left in a box with silica gell packets would be best) it would be permanently marked/distorted. Best written off.