Between his 1953 and 1955 seasons with the Cardinals, Elliott spends an unexplained season in San Diego as a member of the independent Padres. The Redlands Daily Facts of April 9, 1954 has the facts...
“San Diego obtained first baseman Dick Sisler, pitchers Eddie Erault. Cliff Chambers and John Romonosky and outfielder Harry Elliott from the Cards in the Alston-Luna deals. And the Pads still have two more players coming outright from the sales.”
Chambers, Romonosky and Elliott were sent to San Diego for Memo Luna, a pitcher. Chambers finished his career in San Diego that year, but it seems Romonosky and Elliott stayed controlled by the Cardinals. Couldn't find any other players sent to the "Pads." Elliot made the parent club in 1955, but was sent back to the minors for good afterward. From the December 2, 1955 Desert Sun:
San Diego was a Cleveland AAA club that year. Elliot started 1957 there, but was injured in spring training and didn't make the regular season field with San Diego. From the April 9, 1957 Port Angeles Evening News:
"Veteran San Diego Padre, outfielder Harry Elliott fractured an ankle Monday in a Pacific Coast League exhibition game with Portland. Elliott, who was sliding into third base following his first extra-base hit of the spring, will be out of action six weeks or longer."
By the time Elliott was ready to go, there was no room at the inn, and he was sent packing to Vancouver. Via the Ellensburg Daily Record of June 21, 1957...
“Vancouver bought Harry Elliott, the PCL 1954 batting champ, from San Diego.”
Elliott finished his career in the minors at the AA level.
Chambers and Romonosky from www.baseball-almanac.com