You are very welcome quote this information. I am sorry I can’t give you much more. I would definitely read the church history. Those sorts of books often mention key families in the local area, and you might just get something from that.
I have one other source for you. Ballygoney is in the parish of Arboe. It’s in Co Londonderry but very close to the county boundary and straddles the border, so many of the townlands are in Co. Tyrone.
If your Orr and Thompson ancestors were farmers, and had descendants who stayed in Ireland, they would likely be listed in the tithe applotment records. The tithes were land taxes, and so consequently most people with land (ie farmers) would be listed. (Just the heads of household are listed). I have attached the 1826 tithes for Arboe parish which includes Ballygoney. You’ll see a couple of Orr and Thompson farms there. If you get no other leads you might try tracing those farms forward, using Griffiths Valuation, the revision records and the 1901 & 1911 censuses. And if there’s anyone living in the area today, you could approach them for a DNA test. Can’t say whether they’d agree to it, but they might.
http://www.cotyroneireland.com/tithe/ardboe.html
Presbyterian emigrants in the 1700s often came from a farming background (and were often a little better off financially than the average person) so you might expect to find the families in the tithes, assuming there were descendants still living in Ireland in the 1820s.