This seems to be a known issue, but obviously there has been a major toxic gas leak or other serious incident in the customer support which cease them to answer. (I have reported this 2 weeks ago).
Jyri T replied to bwanamikebrown's topic in Toast 19
I have confronted the same issue both with Toast 19 Pro with Mac Mini 2018 (Catalina) and Mac Book Pro 2018 (Big Sur).
The download link link is genuine Roxio support link and Toast version 19.2.