I think you may be mistaken; I am not convinced that the Robert Simpson you describe is the one born in 1834.
Go back to LIBINDX, and in the People Search just put Ch173 in the 'Headstone reference' box, and search. This will give you six results, not including a Jane Christie or Simpson. Have a careful look at them, because I don't see any reference there to Inverness or Elgin or shops. They seem mostly to have been farmers in the Enzie. I presume that you know by now that Chapelford is a Roman Catholic burial ground.
Robert Simpson, son of Peter Simpson and Jane Christie, was baptised in Speymouth in 1834. His siblings were apparently Peter, 1836; James, 1839; Ann, 1841; Andrew, 1843; Margaret, 1844; Hellen, 1846; Alexander, 1850; John, 1852; In 1841 the family were at Drumbain in Rothes. 1851 the family were in Speymouth, but Robert was probably in service in Elgin as an agricultural labourer. In 1861 the family were in Garmouth, not including Robert. In 1881 they were indeed at Newtonbrae, Enzie. Peter seems to have been a farm labourer or carter in every census, not a shop proprietor.
All this except the 1881 census is from free online sources, i.e. LIBINDX, FreeCEN and the IGI. You should be able to replicate these searches. Peter Simpson died at Newtonbrae, Enzie in 1895, and Jane Christie or Simpson died there in 1882.