Suzanne
I have done another search of the townlands of Ireland. Out of about 63,000 townlands, more than 5,000 begin with the letter "D"!
My search of County Armagh comes down to these six possibilities. As I said, there is no place called Durrendrah, but these are the nearest:
DERRYVAUGHT Parish of Mullaghbrack
DERRINRAW Parish of Tartaraghan
DERRYVAR Parish of Tartaraghan
DERRYVAUGH Parish of Tartaraghan
DERRYAUGH Parish of Tartaraghan
DERRYDORRAGH Parish of Eglish
So this narrows it down to three parishes. I hope this is of some help to you.
Marian