I'm running into some issue, i tried the filter and initially that worked, i could see some additional text strings being appended to each result.
That was about 6 days ago when it worked, and today it stopped working. Of course my thought was did I do anything that could have changed it, i did make a bunch of settings changes to how things look but didn't modify filter function you provided in the gist.
I double checked the $id matches, and modifying the copies of results templates in my themes folder still works as does everything else.
I have Query Monitor running, and don't see anything being hooked in, can you recommend a way to debug this?