Marcus,
Unfortunately, as you know, the records for Kralik, Rindskopf, and many others appear to have been lost or destroyed. Empirical research, primarily based on unique shapes and decors, has indicated that the arched mark was used by Kralik, and an example of the mark has not to date, been found on a decor that can be directly attributed to another maker. Unless lost records are discovered, that is about all we will have to go on. Continuing study looks to further substantiate the position, or to uncover a piece of glass that will disprove it.
Regarding this particular piece of glass:
Although the decor of the grill is typical of earlier pieces, the glass is most definitely ca. 1930. It is also possible that the metal grill is a marriage. I can not recall seeing a piece of glass in this decor with a grill of this sort previously. It actually does not look right to me.... It is like 1900 meets 1930.
Craig