Consul is a totally different thing to Cassandra. Consul could be built on top of Cassandra, but it would not provide any advantages. Why would you want to maintain a separate datastore?
Consul is a single static binary that uses around 11MB of RAM. Cassandra is a complex distributed datastore that requires the JVM and uses many gigabytes of RAM.
Our rep said the same thing even when we insisted they rotate our certs on day 1.
Of course we're still waiting. I don't know who's decision it was to not reissue all certs on day 1, but this is an epically bad decision bordering on gross negligence.
I think you're missing the point here. I don't know what else can be explained better.