By 1963, the “Rokal” structures were no longer in the catalog, but it appears that these buildings had been made for them by another manufacturer. Various sources identify that company as “Vau-pe”, but they might have been by “Klei-we”. Regardless, some of the structures also later appeared in the Faller product line as small H0 structures.
In other cases, structures were marketed as being for either TT or H0. I have a Vollmer modern station that is marketed as such, with the difference being determined by the kit builder as to station platform height and doorway height.
Also, there are some European-style structures that appear under the “Berliner” brand. And, in recent years, there have been some Faller structures that are scaled exactly to TT-scale proportion.