I’m certainly not an expert in these things, but note that the first reason listed isn’t confusion with Zoom Video, it’s the lack of public disclosures.

The rule 15c2-11 they refer to requires brokers to have those disclosures on file before processing transactions. This reads to me like a warning to brokers that any Zoom, Inc. trades they processed were very likely in violation of regulations.

Again, this is from a quick reading from an amateur. If this actually affects you, consult real professionals.