Not sure what "list" you speak of but the deal with them is no country that has them in their waters have any CITES quotas for them and with the US being a CITES member nation, we are not allowed to import them. Any that are have been smuggled and the smuggler and even the one possessing them can be convicted using the Lacey Act.
That might be true if these were bald eagles, and you could easily identify them...
Truth is most US fish and wildlife agents know very little about coral identification. Couple that with overseas vendors who also know very little, and language barriers... Well some Rhizo's will just come in every year as a component of stony coral collection, and are cleared by US Customs and US Fish and wildlife. Are they legal, technically no, but they were not smuggled, just mis-identified, possibly at several steps in collection, export, and importation. Are Rhizo's smuggled on purpose? Probably so by a few wholesalers who knew they could get away with it.
CITES was developed to track corals and put limits on collection of a threatened or easily over-exploited (not necessarily endangered) resource. I have not found any reasons why Rhizotrochus are not a CITES listed species, probably just due to not enough information on natural distribution and populations in the wild.
There are many other cryptic stony corals that have no CITES that come in on live rock every week, or are collected on rock with other target corals. But nobody cares about these since they don't sell for big bucks, or they are just too small to be noticed.
Just my opinion, but I think its a big deal about nothing. There are so few of these corals coming in, it is not the big scandal it's been made out to be.
I think more attention should be paid to Ricordea rock smuggling from OUR natural resources in the keys. Or illegal Cuba Ricordea rock coming from Canada. And the practice I still see on occasion of several Blastomussa wellsi colonies being glued to one rock and passed off as one colony.