17K AG pool, High pH, No Chl or CNY, Visible algea

I've been doing BBB method by learning & using this forum for years. I'm trying to help friends who just had a 17K gallon, AG, vinly pool, with sand filter (don't know the size) installed in Indiana 1-2 months ago.
They have visible algea, a very high pH, and can't keep Chlorine.
I tested with my good kit last night (they now have one on order) asked them many questions, here's what I've got.
Chl: 0
pH: Hot pink way over my 8.0 kit can measure
TA: 180
CNY: less than 30 (I can't measure below)
water temp ~80deg F

What I've learned --> they had clear water, have used the pool through July, using it less in Aug, then it turned green. They've attempted to bring the pH down with muratic acid, they can briefly get it down. They have added algecide (not sure what kind, I have polyquat on order), they have added bleach (only 1 gallon at a time, I told them not enough) I recommended 4 gallons to start step #1 below.
I don't think they've ever had stabilizer except whatever would have dissolved due to the pucks or "shocks" they use. They have used oxy shocks but now I have that stopped.

Here's what I recommended to them but I would really like a gut check because I am worried about the pH and not sure if/when to adjust it, before or after CNY?

#1: add liquid bleach/chlorine to get up to 10-15ppm, and do it until you can hold 2ppm overnight
#2: continue to brush & filter & vacuum out algea as it dies
#3: adjust pH with muratic acid
#4: add stabilizer

Any changes or other recommendations I should give?