Denice,
If Margaret died in Ireland, her death in 1884 should be in the statutory death records but I don’t see one in the Clonoe area (Dungannon registration district). There was a Margaret McCorkell of the same age who died in 1884 but she died in Malin, Co. Donegal on 9th May 1884. Her husband was William McCorkell, a labourer. Possibly just a coincidence?
I checked the tithe applotment records for 1827 and I don’t see the surname McCorkell in the parish at all.
https://cotyroneireland.com/tithe/clonoe.html
Likewise there isn’t a single McCorkell in Co Tyrone in Griffiths Valuation (1860). A handful of McCorkells in Tyrone in the 1901 census. All originated outside the county. How sure are you that your family come from Clonoe? What’s the source of your information?
For baptisms and RC marriages before 1864 you need to check church records. You haven’t said what denomination the family was. Clonoe Church of Ireland has records from 1824, the RC records start in 1810. Nearest Presbyterian churches look to be Stewartstown 1st (records from 1814) and Stewartsown 2nd (records from 1827). The Church of Ireland and Stewartstown 1st records are in PRONI (the public record office) in Belfast. Stewartstown 2nd’s records are still held by the church so you would need to write to the Minister to check them. The RC parish records are on-line free on the National Library site:
https://www.nli.ie/en/family-history-introduction.aspx
