How did Irv know?

Forgive me if this was common sense but I felt it was worthy of posting in case anyone missed it (or even better if someone can negate the theory).

So we all know MDR has always been about refining numbers into bins—numbers only. When Irv has his dream in the snow, the images that appear on his screen are like the same jumbled numbers as always but also have some letters within. Oddly enough (at least as far as I can see), there are no letters except E-G-A-N. It never directly spells out EAGAN but I only saw those 4 letters. Is that how Irv was so quick to know that Helly was an Eagan? From his perspective, I can’t recall there being any hints that pushed him to such a concrete revelation. Thoughts?

EDiT: I only saw those “4 letters” not 5. Ha I counted the A twice.