Hi Margie! I see there's no answers yet on DK-60a, so here's some old "Photo Lab Index" data: "(Kodak DK-60a) Kodalk Deep Tank or Machine Developer for Roll Films, Film Packs, Sheet Films and Plates." For developing, they said, "Develop about 7 minutes at 68 deg F in a tank of fresh developer.".(posted 8975 days ago)The formula is (for 1 liter of final solution): Elon (same as metol, I believe) = 2.5 gram, sodium sulfite = 50 grams, hydroquinone = 2.5 grams, Kodak Kodalk (sodium metaborate, I believe) = 20 grams, and potassium bromide = 0.5 grams.
This formula is more similar to DK-50 than anything else I can find; however, there are two differences. DK-50 has less sodium sulfite (at 30 grams) and only half the Kodalk.
Regarding properties, I have no experience, but am willing to make some guesses. I doubt that the sulfite level is high enough to have a significant solvent effect. The doubled Kodalk should raise the pH, possibly enough to get the hydroquinone working. So I would guess that it is basically a little more activity and contrast than DK-50.
The scarcity of information seems to indicate it might not be available anymore; I wonder where she got it and if it's even worth experimenting with?