I have read a number of Ericsson's papers, and most of the Cambridge Handbook; where do they say an equal number of hours of indiscriminate practice is best for beginners as compared to the equivalent effort devoted differently?

I am not, nor have I ever advocated indiscriminate practice as a preferred form of training.

Certainly I agree that beginners benefit most from lots of time spent practicing (total time practicing was a powerful predictor in the studies), but the anecdote in OP was not about two groups of students, one who studied 1 hour a week and the other studied 1 hour a day...

This isn't about time spent. This is about what goal the participants have while doing the activity, with all else being equal. 'Quality' is, empirically, a terrible goal for beginners to be given.