A combination of posting late and bad phrasing, which needs both an apology and clarification.
Clearly, pieces marked with the Tchechoslovaquie impressed mark pre-date 1939. What I should have made clear, is the dark colours were produced pre-war, but do not appear in the immediate post-war list of colours. I know that Inwald used at least two trade-marked opalescent glasses, and probably others. "Duritopal" was used predominantly for utility ware, though that does not preclude its use for decorative items. Another type, which, according to Jackson's "20th Century Factory Glass", was called "Transopal" is likely to have been the metal used in the second of your comparative images.
"There is no mention of enamelled or laid-on colours". Sorry, I did not make it clear that whatever the nature of pre-war production, at the point in time the article was written, there did not appear to be discussion of the above techniques.
If their use returned, I think it would have been much later at Libochovice. However, as you rightly observe, the quality of the moulds was not a patch on the earlier items.
With regard to the silver finishing on your blue vases, might I suggest that the method of application is not electroplating, given the non-conductivity of glass, and hence its use for electrical insulators.
When I worked in the UK ceramics industry, Johnson Matthey made a decorating lacquer or solution, in which precious metals could be suspended, and then be painted onto an item. These were then carefully re-heated, not to a very great temperature, the solvent being driven off, leaving the precious metal bound to the surface. I presume the Czechoslovakian glass and ceramics industry must have had access to something similar.