Okay, the book on the monasteries of this region was actually authored by Dr. H. Hamazasb Vosgian. At least that's how I would transliterate it knowing he's Armenian. It was published in Vienna. The entry on Yeghrdut starts on page 91.
The "Dictionary of Toponymy of Armenia and Adjacent Territories" is published in Yerevan. The Yeghrdut entry is in Volume II, which came out in 1988, and is on page 193-194. Authors are T. Kh. Hakobyan, St. T. Melik-Bakhsharyan, and H. Kh. Barseghyan. Published by Yerevan University Press.
The dictionary tends to be extremely detailed in listing every possible name a place has ever had. For this monastery, it does not list Dera Sol, or Karmir Vank, or anything else that seems to refer to the name "Red Church". The basic name variants are: Yeghrtud, S. Hovhannes of Yeghrtud, Yeghekni S. Hovhannes, Yegherdur, Yeghrtuto, S Hovhannes, S Hovhannes Mkrdich, Shishivgho, Shishyoghu, Shishyugho... it lists more, which are very minor variations on these.
The coordinates I gave were a guess just by reading the directions and then looking on Google Earth for a spot that might match the description. It turned out to be quite close, but not quite on the dot.
Hope that helps,