I first encountered Mr Jewell's name on a Russian web-site that I came across earlier this year:http://footballfacts.ru/referees
This is a vast data-base with a wealth of information about match officials, although you may wish to note that the site is Russian (but with the possibility of searching for names in either the Cyrillic or the Latin alphabets) and is not particularly easy to use. Not surprisingly the coverage of Russian and Soviet football at both national and local levels is the most comprehensive: I first discovered the site when I was looking for information about the Moscow city championship in the 1930s (please don't ask why), while that of British domestic football is distinctly patchy. There are, however, two positive features about the site: the first is that more often than not information is given about linesmen, as well as match referees, while the second is the inclusion of a considerable information about international fixtures, some of them quite obscure.
For Mr Jewell the site currently lists 18 fixtures in which he was involved either as referee or as linesman. The only domestic fixture is the 1938 F.A. Cup Final; among the international fixtures are the 1938 friendly between England and Europe and the matches at which he officiated during the 1936 Olympics (as mentioned in the radio programme), but there are also Home International games, as well as various other international fixtures, both competitive and friendly and even two games in the Mitropa Cup (which for those who have temporarily forgotten was a club competition involving teams mainly in Central Europe).
By following random links it is possible to stumble across a remarkable amount of extremely arcane information. Whether the site will provide the answers to questions that people are asking still remains to be tested.