A very large proportion of faults are due to simple bad connections.
When an LCD panel wholly or partially loses its display, one of the possible reasons is this:
Some LCD glass panels are connected to their driving PCB only by being pressed onto rubber strip connectors which have conductive strip through them.
After even a small knock, the glass LCD panel can be jarred out of alignment with its rubber strips, and therefore wholly or partially disconnected.
The remedy is simply to disassemble and reassemble the unit (rather fiddly job, keep everything _very_ clean), and (hopefully) all will be well.
It is very rare for an oscillator crystal to fail, much less blow up. I second Eugene's idea that we need a good close up image of the suspect part. Use a magnifier in front of you camera lens if you don't have a close-up lens.
Also please provide a good image of the LCD display screen,
The only way to get the specs for the part is from the manufacturer of the display unit (which might be the same maker of the UPS), if they have a helpful technical support department.
If all else fails, you could remove the suspect part and try connecting a few different crystals to see if it makes any difference. But this would only be a desperate last resort.