The city came by to look at my driveway and a small hole that opened up creating an unwanted secondary drain into the sewer. This hole was further down the line on the same storm drain. They filled it with sand and filled some sand along the edges of my driveway where a couple spots seemed to be sinking in a bit.

I unfortunately did not get a chance to speak with the workers so I have no idea how well they inspected the driveway. I posted some borescope footage with my findings below:

There appears to be a 2-3 foot wide channel that runs parallel to the expansion joint, about 1.5 feet deep. The 2 pieces of driveway seem to be cantilevered over this channel.

It almost appears like it was an intentional design, although there are areas where that solid wall have receded with nothing actually under the concrete. I found tree roots everywhere which was expected. This void sits about 10 feet further up the driveway than I believe the storm drain runs through.

At this point, I think my next step will be contacting a company that can get a better look and give me a better idea of what I'm dealing with. If any work needs to be done that is related to the storm drain, I believe they'd be able to provide more evidence for the city to possibly get involved. 

Thanks all for following. I didn't expect this to garner so much attention lol 

[Follow up] What is holding my driveway up?