Hi,
I looked in Ancestry for any Walworth's living in Bannock Co. 1889-1909 but nothing came up with the initials A. G. or applicable first names.

You can check with the South Bannock County HIstorical Center Museum, lavahotsprings.com/museum.htm or the Bannock County Historical Museum & Society, manta.com/company/mmcr541.

The Pocatello Branch Genealogical Society, PO Box 4272, Pocatello, ID 83201 might also have some information. Successful Searching!