I got broken headphone jack removed, now headphones don't fit in jack

Hi Callen,

Assuming there was no damage to the motherboard from the broken headphone jack and it's already been removed, the it should theoretically be a fairly simple job to solder a replacement port onto the motherboard.

First thing you need to do is locate a suitable replacement part. There's a website called accessoires-asus.com that sells parts for Asus computers, and they do have the jack you need.

accessoires-asus

Once you have the replacement part in hand, the next step is to remove the motherboard from the laptop so it can be worked on.

Asus Chromebook C523N Motherboard Replacement - iFixit Repair Guide

You'll see a square cutout where the jack mounts; it will need to be soldered in place there. If you feel you have the soldering skills then great, go for it; otherwise you may want to consider taking it to a shop to have the actual soldering done. For a repair shop this should be a simple, straight-forward repair so I would think it shouldn't cost you an arm and a leg.

Here's the motherboard with the audio jack in place.