W. Darrin Weaver's "Hitler's Garands" indicates that as a result of "the decision taken by the Mauser Abteilung 37 office to include as many K98k parts as possible," the cleaning rod for the G41(M) was intended to be the same as that of the K98k. Until about 1940, that length was about 10.5 inches. However, Mauser made 12.5 inch cleaning rods starting in about 1941, and there were multiple memos regarding various design and manufacturing decisions issued by the Mauser Abteilung 37 office over several years. I suspect that some rifles were issued with 10.5 and others with 12.5 inch rods, but in either case they were simply taken from the K98k production line, and no unique G41(M) cleaning rod ever existed.
Standard cleaning rod would only make sense....The policy of the Germans at the time was to link multiple rods to make one long enough to go the length of the barrel....Would be no reason than to manufacture a special cleaning rod for the G41(M)...Bodes