Right now, the only two weapons that we've confirmed to be compatible with the UVLS is HHQ-9 and YJ-18.
There are no indications that the PLAN's UVLS will favour CASIC products, nor am I 100% confident that the HT-1E is actually the export variant of the PLAN's proper UVLS to begin with.
As for the FM-3000N itself, I have nothing against the weapon shown, but I feel like if it were the 3-5 missile, then someone with a track record would've made more noise about its identity, which is why I hold significant doubts.
There are of course a number of candidate missiles we have seen on export that might be a candidate for the 3-5 missile, but it is also very plausible that it is simply a clean sheet design as well.
U-VLS is CASIC's creation. Obviously U-VLS will favor CASIC products. The HT-1 is displayed in CASIC's area in the Zhuhai air show hall.
The model is as official as it gets, so it confirms more missiles slated for the U-VLS including CM103. HT-1E with the "E" is the export variant, which means its real name is HT-1. This goes with the new style that export names are getting "E" added. Instead of "FL9000N" for example, you get "HHQ-10E". This is for marketing purposes. Customers want something the PLA is using rather than an untried product.
Because a good majority of the PLAN's missiles are from CASIC including HHQ-9, YJ-83, YJ-18, HHQ-10, they got a strong inside track in winning this contract. CASIC can also be called the PLAN's missile supplier with a few notable exceptions.
Those notable exceptions are from CASC, which is more noted for their space and satellite work, but is also doing missiles. They are responsible for the HQ-6 and HQ-16 systems. We see them offering this LY-70 now which looks like an ESSM sized missile and is packed in sets of four in land delivery.
Now for this "clean sheet design". Even the FM3000 started as a clean sheet design with no direct connection to any previous missile design. We don't really know if missiles like FM3000, SD30 or LY-70 started as land based design adapted to naval base, or is it they started as a naval based design adapted to land based. People might want to get the maximum out of their existing products so its not surprising a naval system like Type 1130 CIWS is adapted into a land system. Missiles can start being conceived as a universal land-sea design, then split into variants.
It would be a tremendous waste of effort to design a brand new missile solely for export, not to mention the system reaching the deployable stage. If the missile is a failure, rejected for whatever reason, it should not reach to the point you want to sell it to customers. It would have been weeded out early, so you can throw your financial and human resources to the survivor and chosen champion. It does not make sense to me to continually developing a non accepted design in parallel with the chosen design to the point that the non accepted design has reached an export status.