Discourse on the nature of Dakruko: 

There is some uncertainty when it comes to whence the quote heard originates from. Initially, I was predisposed to attribute the quote to ancient Sumerian, where (at least indicated by recurrent myths and legends profusely evident in the region) the being whose name may be rendered as Daekrooko was regarded as some demigod of no little personal strength.
It is uncertain whether this person was real or not, as prolific examples clearly shows that many of the "god-kings", like Gilgamesh (a figure in the pantheon of old Babylonia), either were legends, like the Greek Heroes (Jason and the Argonauts, Hercules, and so on), or exceptional individuals whose above-average stature elevated them to a godly status.
As far as I am concerned, this is not something that may be ascertained at this time or date, and these are the only references made to any entity having a name even phonetically similar to the second word overheard by your source. I must also admit that I would very much like to meet with this individual, if for no other reason than to get a first-hand recounting of the incident that led to the utterance of this rather peculiar - but interesting - quote or invocation.
I say "invocation", as this is the most fitting word in English for it. The second part of the phrase, or indeed, the first part uttered, that may be rendered in English as "aghrawaat", is something of a linguistic double entendre, as it has similar, but widely differing meanings in various now-dead languages. Indeed, I cannot find any single language now in use, except for the exception noted below, using the word or, indeed, having it in its vocabulary.
There are several possible translations for this word, allowing for phonetical mispronounciations, but I found a small group of languages that was convergent, at least for the intent of the phrase.
The most interesting case is Nepalese (hardly a scientific name for this unique and interesting language, yet accurate enough that a non-linguist like yourself get the gist of it), where the word has meanings similar to "help", "benefactory action" or "(divine) aid". It is concidered archaic, and is no longer actively used, even though it has a place in formal proceedings during religious ceremonies.
Another case is ancient Sumerian, where the word may be translated as "help" or "action in which the (pronouncer) offers his (the term used loosely) thanks to an aiding person". This last may look like a strange rendering, but this is due to the rather recursive approach the ancient Sumerians had to their language syntax.
The last case of any approachable incident, is an obscure Indian dialect of which I just happened to be researching on a grant given to me by the University. The world has a function in a formal prayer to a local power, "the black (sorcerer being the closest translation)", that asks the (sorcerer) to use his power to aid and protect the utterer of the prayer, namely: "Aghraw'at din'r zhagott' wahat, d'ah kri-kah", where the last part is d'ah (the black) kri-kah (sorcerer).
I am sorry that I cannot come up with anything more substansial, but I hope this will help you somewhat, and I also hope that you will consider my request to meet this individual overhearing the phrase.
Yours sincerely,
Gerald. (Dr. Gerald Quatermass, professor at the linguistical department of LA University)