First, I’d like to draw your attention to the @NameLookup function.
Can you please revisit this code and make sure it’s an exact copy of what you’re using? It doesn’t pass syntax check, and I don’t see the name ClntMachine in it anywhere.
From looking at my own names.nsf record, it appears that the most recent client is listed as the last entry of the multivalue field ClntMachine. Use @Subset(…; -1) to pick out the last one.