Frankly i have no idea where get the idea why people think daino scrolls lvl 15 is going to be hugely popular. Pretty much it’s all theory crafting and assumptions, but very few actually even bothered to test it out.
Demand for lvl 15: Yes, probably as more buffs get introduced into the game
However: Nobody is going to fork over 11k for a 3 min scroll on the market.
From my experience in ICBT2 (I was like the poorest pardoner on the server cuz i went krivis/pardoner), most people would just settle for lvl 5 - 10 scrolls as they get the job done without the high cost. Even then the amount of daino scrolls and zalc scrolls that i sold over the course of the beta numbered below 50 scrolls -_-. You would also have to factor all the int type cleric builds that will actually use krivis (sadhu, druid, pd, and etc) as competition.
It’s pretty stupid to say that might change on the future. In it’s current state, it’s vastly more profitable to go spell shop pardoner. If your like the first spell shop pardoner then you’ll be rolling in the money. It was disgusting how much money he made 
Even with all the problems, i probably still go krivis/pardoner (might not even get simony next time around because it wasn’t worth investing an extra 14 skill points to barely make any money) to break up the monotony of priest/pardoners in iOBT. Though i might scrap krivis pardoner if they don’t add more skills to c3 pardoner or improve on it. At least, i won’t be the only unicorn in the game :D.