no sign of a marriage in Ireland in civil record based on the BMD Index, the only Matthew Warren marriages (far less common a surname than Barry) anywhere in Ireland for the right timeframe are in Lurgan district (Antrim/Down/Armagh) in 1868 and Dundalk district (Louth) in 1871, and neither cross-match to a bride with the surname Barry. I also checked all Warren marriages between 1864 and 1878 in the New Ross registration district, which covers the Ramsgrange area and none of these cross-match to a Barry either. There are a few other male Warren marriages listed for the other districts that cover Co. Wexford, which I'll have a look through when I get a chance..
Since there's no specific data on a location for Matthew I'm wondering if his family came from another part of the county. Just a handful of parish records for the county are included on RootsIreland at the moment, including Templetown aka 'St. James & Templetown' or 'Hook & Templetown' which covered part of this area (I'm assuming RC for this family..). The adjacent parish to the north was St. James & Hook/Ramsgrange which RootsIreland do not include at the moment, so so might be worth keeping an eye out for updates for that site.
I would suggest another trawl of marriage records in England, particularly RC parish records in case Matthew and Catherine missed out on a civil registration, and in addition RC parish records in cities like Manchester often include useful detail not on civil certs - e.g. both parents names, addresses in Ireland etc