One problem with pre-War cameras is that some were often re-badged for distributors, Zodel was Wallace & Heatons brand, Sallex - City Sales & Exchange, Wellex - Westminster Photographic Exchange, and that's just the tip of the iceberg, each name embossed lust like yours.
Not sure what date the Prontor name came into use, after Compur switched to Rinset rather than Dial-set though, so after 1929 and the adoption of standard shutter sizes, but the Rodenstock lenses are fitted in either Compur's or prontor's and the even cheaper shutters that AGC made like the Vario,
Ian