If you do a search on PRONI for freeholders you will see 2 entries for Moffitt in Drumschool:
Surname of Freeholder Moffitt
Forename of Freeholder William
Address of freeholder (townland or street) Drumschool
1796
Surname of Freeholder Moffitt
Forename of Freeholder William
Address of freeholder (townland or street) Drumschool
1788
It would imply that this William Moffat was the probable father to Margaret. I would suggest looking at the names of Margaret's children and the children of the possible siblings in Drumschool. My 2X great grandfather and 2 of his siblings who immigrated earlier did not follow the traditional Irish naming tradition. His brother who stayed and married in Ireland did follow the Irish naming tradition. It took a few years of research, but I was able to corroborate the names.
https://www.irish-genealogy-toolkit.com/Irish-names.htmlWhile the siblings who didn't follow the Irish naming tradition for first names, some of the children's middle names did correspond with grandparent's and great grandparent's given names and surnames.