I know this sounds crazy, but the builder may want your building to be unstable. It is then deemed unhabitable and he buys up the property from the current owner. We saw something similar in the PAD.

Is there a permit hanging anywhere? The bright yellow ones? If so, you can trace the info per the building dept website.
Get all the neighbors affected by the damage together, strength in numbers.

Call a lawyer, duh.

I own one of the buildings between Grove & Grand. Back in 2015, construction on 28 Bright Street (Parking lot being converted to condos) caused a neighboring garage to collapse and caused some major headaches in the neighborhood. A few days later, i found 3 crack gauges/meters glued to a few cracks outside my building. It wasn't just my building, someone had installed these crack measuring gauges all over the block (Bright/Barrow/York/Grove). Later I found out that these meters were installed by the developer of 28 bright street (via an engineering firm) to ensure that the collapsing of that garage is not causing further damages to the neighboring building.

I am try to get some documentation from the city on that and any concluding study/findings from that engineering firm but not having much luck. Anyone have any insight on what's the best way to move forward? Thank you very much!!!