Tradition was to marry in the bride’s church so if the couple married in Clonoe parish, then probably that's where Elizabeth was living in 1875. The Muldoon family appear to have been settled in Elagh for some time before 1875. Joseph’s birth in 1876 was registered by Jane Corr of what looks like Rooskeane. So that may be a clue as to her origins.
https://civilrecords.irishgenealogy.ie/churchrecords/images/birth_returns/births_1876/03037/2113365.pdf
Elizabeth Muldoon (nee Corr) died in 1901, aged 41:
https://civilrecords.irishgenealogy.ie/churchrecords/images/deaths_retu…
Bernard and family in Elagh in 1901:
http://www.census.nationalarchives.ie/pages/1901/Tyrone/Killycolpy/Elagh/1732096/
1911:
http://www.census.nationalarchives.ie/pages/1911/Tyrone/Killycolpy/Elagh/861700/
Griffiths Valuation lists Bernard McIldoon on plot 11 in Elagh in 1859 That was a farm with 2 separate chunks of land near each other totaling just under 11 acres. I’d guess that was Bernard’s father. That farm today is on the modern Ballymaguire Rd. It’s still a farm (judging by Google earth) but some of the old hedges have been removed and the area enlarged a bit.
http://www.askaboutireland.ie/griffith-valuation/index.xml?action=nameSearch
Bernard died in 1916. The informant was his daughter S. Creighton of Mullaghglass. So a clue there as to where 1 daughter went.
https://civilrecords.irishgenealogy.ie/churchrecords/images/deaths_returns/deaths_1916/05246/4454194.pdf
Here’s Sarah’s marriage to Robert Creighton in 1916:
https://civilrecords.irishgenealogy.ie/churchrecords/images/marriage_re…
The Valuation revision Records on the PRONI website show the farm passing to James McIldoon (variant for Muldoon obviously) in 1919 and he was still the owner in 1929 when those records finish. A Bernard Muldoon appears on plot 12 in 1926 (until then owned by Thomas Badger).
There was a Hugh McIldoon farming in Elagh in 1826 according to the tithe applotment records. Presumably related to the Bernard who had the farm in 1859.
http://www.irishgenealogyhub.com/tyrone/tithe-applotment-books/parish-of-arboe.php
There are 3 possible deaths for Bernard Muldoon senior 1864 – 1870 but they are not free to view so can’t say whether it’s your family.
It’s not our policy to give out information on people alive today but if you look in the UK phone book, under postcode BT71, you will find several Muldoons in Ballymaguire Rd. So I would guess the farm is still owned by the family.