Hi @robeso ,
Not disconnecting the battery was not a good idea.
Isopropyl Alcohol IS conductive to electricity when it is still wet and hasn't evaporated yet. The good thing about it is that it leaves no residues, conductive or otherwise when it has evaporated.
You would need to check the motherboard for any component damage and if none obvious then you would have to search for the motherboard schematic to hopefully find them so that the circuits can be tested etc. Search online for ''(insert motherboard 'board number') schematic.'' The board number is printed on the motherboard.
Post some close up images of the motherboard. Maybe someone will spot something if you can’t. Here’s how to do this [guide|21499]