Hi blueray and welcome to the forum.
Since you've started the Maracyn course, I'd recommend finishing it but just to let you know, Maracyn and Maracyn II aren't effective if you have a pH over 7.3 or so. TheCheese is right, though, that usually you want to start with conservative treatment but I do understand that Blue Ray is your pet and you want to do everything possible for him. :) However, sometimes too much medication does as much harm as no medication at all.
In general, you don't want to add AQ salt to the water unless there is a definite reason to. Long-term use of AQ salt can potentially damage the internal organs, as freshwater fish like bettas are not meant to live in brackish water.
Go ahead and do 100% changes every day during the 5 day course of Maracyn II and redose the meds each day. If he has not shown any improvement at the end of the course, give him maybe 2-3 days in clean water with no additives except for the water conditioner. Then put him in AQ salt for 7 days at a dosage of 1 tsp per gallon.
If you have Indian Almond Leaf, I'd highly recommend using that too. Naturally dried and clean oak leaves will work too. Just crumble them into the water until it turns a tea color.
Good luck and keep us updated!