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The Inishowen Peninsula is in North Donegal https://en.wikipedia.org/wiki/Inishowen#/media/File:Inishowen_peninsula.PNG and would be a good distance from Drumhome civil parish which is in the southern part of Donegal just below Donegal town.
More than likely your Quigley line is from Inishowen based on the Griffiths Valuation data I located. There are also a good number of Harkins up in Inishowen. Quinns would be more from the south of Donegal.
Regarding RC records, most Donegal parishes have records that start late and Drumhome parish starts in 1866.https://registers.nli.ie/parishes/1005
Let me know what other questions you have.