I do see old demolition permits. This web tool can show where building permits and demolition permits have been applied for, but I find it is not very helpful on the details:
A landowner can demolish a non-residential building as-of-right in Toronto, which means the demolition permits are practically automatically issued by staff as long as basic requirements are met. There is no circulation of the information to the local councillor or any opportunity to weigh in on it. But there are exceptions, including heritage protection. The HCD is supposed to stop any "Contributing" heritage buildings from being lost in this way.
From the web tool, it looks like the demolition application was submitted in 2016, before the HCD came into effect, and generally Provincial legislation doesn’t allow for heritage and planning protections to be applied retroactively.
There were also lots of pictures submitted by contributors to Urban Toronto:
Plans for the 8-18 Camden sites are not available at this time.