Leave it disconnected for another 48–72 hours.
Store it in a warm, dry place with good airflow.
The trackpad has its own electronics and ribbon cable.
A small amount of liquid can damage only this section while leaving the keyboard unaffected.
Test in the UEFI:
Shut down.
Hold Volume Up while pressing Power.
If the trackpad doesn't work there either, it's almost certainly a hardware issue.