That's an excellent observation Rex. I checked it out and came up empty, but I've since got to the bottom of the whole thing.
Just as it says in the Bownian description (in the Bown catalogue, but seemingly nowhere else) the frame set was made by Villiers Engineering Co., Ltd.
The patents for the various interesting design features were applied for and granted to VEC in 1921/22. Specifically named as applicants were VEC, Frank Farrer, and Frank Pourtney, but the "inventor" field was left empty, presumably because the inventors were Villiers employees and had no rights to the designs.
The fork was not a Villiers thing, but originated with an Australian: John Percy MacLean who lived in Newcastle, NSW. He held about 23 patents over the years, including the one for the double-spring arrangement in the Triumph-like MacLean fork. In late 1919 the design was taken over by the Gosford Engineering Co., Gosport, Hants. They manufactured the fork as the Gosford, and presumably sold it (or licensed it) to VEC for their motorcycle.
So who knew? Villiers made (or had made) a complete motorcycle in the early 1920s. It was sold under various brands in the UK and Australia, including:
Beaufort
Bownian
Dayton
Mohawk
Monopole
New Courier (cheaper model of Olympic)
Olympic
Spark
Torpedo (Tasmania, Australia)
Warrior
Wolf
Victoria
Villiers (Tasmania, Australia)
I went through "The British Motorcycle Directory" by Bacon and Hallworth, looking at the above brands. Fair to say that the authors didn't appear know that these makes used "the VEC frame set". I don't have Jack Sizer's book on Villiers, but in his various writings online I can't find any mention of the Villiers motorcycle. It looks like history has skipped it over, which is a pity because there are many modern, clever designs in the frame and fittings, particularly the extensive use of pressed steel for the lugs and fittings, including the petrol tank.
(Or course Villiers could have outsourced the manufacture, perhaps to Gosford, or Sparkbrook, or someone else. Some expertise in and equipment for pressing complex shapes in sheet metal would be needed.)
On the AUstralian front, I now understand why Charlie Hay in Tasmania was claiming in 1923: 'The Villiers is one of England's best light-weight motor cycles."
For the record they were landed originally as complete motorcycles and sold (and registered) as "Villiers", but later they were "built" in house, no doubt from a kit of parts, and sold with the name "Torpedo" on the tank.
Cheers
Leon