Ok, a resolution to this one.
Pattern numbers 20047 and 20048, are by Vizner and Urban respectively.
Ivo's image at figure 8, www.sklounion.com/Sklo1.html
is clearly shown in illustration 13, of the Vodička article in CGR Vol 18, 1963-08, "Pressed Glass: A Supplement for the Modern Interior", and attributed there as Urban.
The confusion arguably lies with the plan drawing in Warmus, as that plan drawing could apply to either vase.
The significant difference between the two vases, is that the Vizner vase (h.190mm), has four oval lenses set at 90 degrees to each other and three horizontal rows. Urban's vase at 210mm, has the lenses off-set, (I hesitate to say tesselated as the shape of the lens is not conducive to that). Urban's vases has five lenses in one quadrant, four in the next, then five, then four.
It is merely a hypothesis, but as these vases are so similar, and date to the same year, that, on the basis of Vladislav Urban's statement his was a graduation piece, I think it possible that both students had been set a task to develop lens/optic vases as part of their final work. Whether they were set the drawing contained in Warmus, as part of the task, and to come up with different designs which matched the requirements, remains to be seen.
I hope this clarifies the issue.