First of all, I would measure your Disconnector length. I suspect it'll be right around 1.296". If so keep it, it's perfectly good. Next, has any adjustment been made to the trigger-stop screw? An improperly adjusted screw( turned too far towards the front of the trigger or worse, removed) will allow the bow to push the disconnect too far and result in Hammer-Follow as it won't allow the sear to capture the Hammer-hooks. Next, when you reassembled after your 'Armorers' Cleaning', did you install the searspring correctly? If not, it will allow the Disconnector to stay up and not reset. This will cause Hammer-Follow. Here's how the Searspring should look if properly installed.
All in all, of the parts you replaced, the sear MAY be bad but, the gun would have to have 10s of thousands of rounds through it for a correctly fitted sear to fail.