Whenever we pass a VALUES clause with too many elements in it, then we always see a set of answers that does not include everything that was provided in that clause. I haven't tried to narrow down how large a group can get through, but I do know that 18 single bindings will work, but 30 will not.
Right now I can get around it by creating a UNION between multiple VALUES clauses, but this seems to slow some queries down quite a bit (though maybe it's just because more data gets processed when everything is included). It's also frustrating to need wrapper code to break VALUES groups up like this.
I think this problem may have been raised verbally a couple of years ago, but I've just rediscovered it while using Stardog Cloud. Is it currently on the radar to be fixed?
Paula