Questionable future for Vienna Ensemble Pro? Hardly, tons of people use it. It's easily VSL's most popular product. I know lots of people who use it who don't own a single VSL library. VE Pro is not going anywhere.
Vienna Instruments though is much more niche, but they did fairly recently get it working natively with ARM-based Macs without Rosetta, which gave it a new lease on life.
I don't have the library in question, but my guess is that probably these issues can only be fixed with a fairly major re-edit of the sample set, which was already done for Synchron-ized and so they don't wan to have to redo it for VI series too.