Hi,
I live in Carmel and am willing to help, if I can.
I'm currently researching the history of the village and am slowly working my way through the Census records.
What I have noticed is that when Llandwrog is given as a place of birth, it refers to the district/area rather than just the village of Llandwrog. So anyone born in Carmel, Cilgwyn or nearby would more than likely be just listed as Llandwrog. On top of that, there is a smaller community called Upper Llandwrog, but that is part of Llandwrog district/area.
As far as I'm aware, the Church of St Thomas mentioned by another poster was Church in Wales. The church has been demolished and the graveyard is pretty overgrown.
There are 2 cemeteries in Carmel, both non-conformist. One is Capel Pisgah and the other is Capel Carmel. There is also an older cemetery but I'm not sure which church/chapel that belonged to. Do you know which religion your relatives belonged to?
I'm happy to have a look at the cemeteries in Carmel for you if that would help but it would be good to know what religion they were as both cemeteries are quite big.
If so, would you mind listing the names and years of birth/death that you are looking for as I've got a bit confused reading through all the posts.
As far as I know Bryntrallwyn and Bryntirion are both in Cilgwyn which is very close by but I have seen them both referred to as being part of Carmel in some records. There are many graves for residents from Cilgwyn, Y Fron and Upper Llandwrog at the cemeteries in Carmel so it looks as though they covered the whole area.