Hi Sarah
Sorry, he doesn't appear in Sawston in 1861, nor was he in Linton Union Workhouse.
Do you have his death cert in 1862, which should give a place of death, and possibly a wife's name if she was the informant?
He may have remarried in 1854 as there is a marriage of Isaac Goodacre in June 1854 in Linton Registration District on FreeBMD. Per the Cambs FHS site what appears to be his first wife Sarah and daughter Caroline both died in 1836.
Regards
David
Do you have full details of the 1841 and 1851 census entries? If not I can let you have them.