Good after noon Rootschatters

After taking a few months off from the old family tree I am picking it up again!
BUT, I have hit a brick wall where my gr gr grandmother came from.
Her marriage was not on SP and I had to wait till the catholic parish registers became available and finally got the date of marriage of 15/07/1864 at St Patrick's Anderson!
She was Margaret Harvie/Harvey and she married John Doherty from Donegal and they settled back there when married.
Unfortunately there is no mention of a father's name on the catholic register only the witnesses so I can't get any further back with censuses etc

According to my mum,gran was adamant that she was from Campsie,but unfortunately she is no longer with us so I can't ask her any more questions.
I thought that maybe there might be banns or the like in a Glasgow newspaper maybe

Maybe some more experienced RChatters might give me some ideas or is this as far as I will get?
They must have moved back to Donegal fairly quick to not have registered the marriage with the registrar.
Regards
Annette