I should have mentioned that the hydroxide is sufficient to neutralize the sulfuric acid attached to the Metol and to convert the ascorbic acid to sodium ascorbate which is only slightly basic. The solution wouldn't do much developing without the borax.
We often substitute 14.5 grams sodium hydroxide plus 69 grams of borax in a liter of solution as 10% sodium metaborate. 276 ml of such a solution contains 4 grams of the hydroxide and about 20 grams of borax, whether you mixed it that way or from 27.6 grams of sodium metaborate. I have tested both ways.