The tribunal has set the precedent that its an absolute responsibility of the OC to repair and maintain common property.
In the poster’s case they have no option but to carry out the repairs.
$200k per lot seems an extremely high repair bill.
As a start the committee needs to get involved and get some other quotes. There are project consultants out there that can write a scope and get quotes. If that’s a help.
The ne t step, after you get quotes, is to figure out how to pay for this. I suggest a loan considering the high amount.
As a last option, you may consider selling the whole building for redevelopment. Right now your equity is about $350k. A developer may pay you more than that .