Jumping the power pads worked ... but ...

long time lurker, first time poster!

My mother spilled coffee on her 2014 macbook air, and thus it wouldn’t turn on. Power cord turns orange and then green as normal. My father ordered a new battery, handed it to me and said put this in i think it will work. I put in the new battery, and still it wouldn’t power on. We bought them a new machine, but this macbook air is in otherwise solid condition and seems too nice to give up on if I can get it running.

I read about the power pads and got excited. i managed to detach the keyboard ribbon, and reattach the new battery. using a screwdriver thingy i was able to get jump the power pads and get the fan to spin, WOOHOO. kinda. The computer would loading and then turns off half way through booting… after a few attempts it did manage to load the OS (yosemite) and see the battery read 100%, but after 30 seconds or so the computer then just goes dead black.

I am here to confirm that y’all think this is logic board issue, or if there may be some other things i could test or replace. I did read that spills on the keyboard can cause shorts causing the machine to turn off…and sometimes replacing the top case can fix an issue - but i did disconnect the ribbon from the logic board, but perhaps it is also connected to the computer power in other ways?

I am willing to put $100+ into this machine to get it running, but a replacement logic board might just be too much. Any advice?