the green howards were or based in Richmond yorkshire and are/were part of the rifle brigade, the labour corps became the "Pioneer corps" up to WW1 each regiment would have had a labour company "pioneer company", the worcester regt is still I believe an indipendent regiment, but with all the political meddling over the last few years could be included in the reorganised mercian regiment. I suspect that there was a military medical clearing station, or hospital near by where these few lad,s passed on. as you say RIP boys.
paul