The BS/ACV is good for any age locks. Just use the right amount in the mixture, and you're set. You don't have to scrub your scalp with that wash, either. But while the BS is in your hair , squeeze the locks that have the residue like you have been doing. That'll help the process along a bit.
It hasn't gotten all of the residue out of my locks, yet, but it has gotten the majority out. It takes time.
And the dish soap should be at any grocery store. I forgot to check if you were in the States. If so, it's easy to find and a grocery store. if not, find yourself a dish soap that is anti-residue or tough on grease.
Fill a pot or bowl of water as warm as you can handle it with your hands submerged. Pour in a generous amount of soap. Dunk each lock in for a few minutes and work the soap in with your hands. Do this to each lock, and then wash them. You might have to do this a few times to get all the residue out, but it'll work. It's not wax, so you should be able to be sure you got it all out after a few of these washes