Iridia

You could try to patch it, but it will be difficult to get an even surface on the inside and it could ultimately damage the liner. You said it was just one of the panels, so it's not one of those pools where it's just one solid sheet of aluminum stretched all the way around? Is there any way to contact the manufacturer to order a replacement panel? More expensive than a patch in the short term, but probably cheaper in the long run if it damages the current liner.

As chemgeek stated, it's the exact opposite: Soda Ash (a.k.a. Sodium Carbonate) raises pH more than TA. Baking Soda (Sodium Bicarbonate) raises TA more than pH.

Add it "when the water feels dirty"? Um, ew. That sounds pretty unsanitary. Does he even test the water? I know the Baquacil system uses H2O2 for its shock, but using it as your only form of sanitation is downright nasty.