Charges phone but won't power on

Just as the title says. A friend gave me their Xbox one s to take a look at it. Apparently their cat !#^&@@ on it… I cleaned the motherboard of all corrosion and swapped out the Rf board. I tried to turn it on by the power button, the sync button, the eject button, using a controller and inserting a disk, but no go. I used a voltage meter and found it was getting power throughout so I plugged my phone in. Charges. Any ideas? Clean heat sink? Reball? <———(can’t afford) Throw it Away? Is it done for good? Thanks in advance!