The issue of alba vs. album has been covered. I would just add that it could also be albus depending on the genus, and the same goes for aurea/um/us and many other terms. Other terms like alboviride do not vary in the same way.
From a quick search of just a couple sources, it appears that Paph villosum var. (or forma) album has never been published. The flask from Sam may correspond to Paph villosum forma aureum. Either album or aureum should refer to a variant with no reddish pigment in this case. A yellow or green flower could validly be called album, as long as the type form does have reddish pigments and the yellow or green is characteristic background color for the species not an usual variant. There is really no rule on that. It depends on what has been validly published.
In this case there is a published name that probably applies, aureum, so it is a bit sloppy to use alba or even album. The problem is, except for maybe about 5 people world-wide, no one knows (or at least has an opinion about) what varieties or forms have been validly published for many species without looking it up. And in many cases the valid form might not be a color designation at all. Paphiopedilum fairrieanum forma bohlmannianum is the recognized name for green and white Paph fairrieanum without any reddish pigment.
In many cases there may be no validly published name to apply to the color form in question. And there is no formal way to refer to color phases of a man made hybrid. It is best to avoid something like Paph villosum album if it hasn't been validly published, or Paph Maudiae alba ever. At all times, a phrase like "an alba form of X" would be correct use of language and not violate any scientific rules, though a little awkward.