Below is a link describing the Veteran Reserve Corps and what they did. I doubt Sweeney
would have been injured serving the VRC. They primarily guarded bridges, enemy prisoners,
and other non-combat tasks.
Your best bet for further information on him may be the pension application @ the National
Archives I referenced previously; and his newspaper obituary from the town he died and
was buried in. The local public library in that town should have it, if it still exists.
Best of luck with your research !