I've used both and usually substitute about 1 quart or so. Since yours holds 8 qts, you could probably get away with up to 2 quarts. I know that MMO states you can substitute up to 20% of engine oil with that. I'm currently using that on my daughter's 2008 Lucerne with a noisy lifter from previous owner lack of maintenance. It has so far quieted it up. It's a slower process as the varnish is cleaned off and oil can flow properly again.
I'd probably start with a fresh oil change and put in 6.5 qts oil, 1.5 qts ATF or MMO. Then let it idle and for awhile and see if the noise improves. If it quiets down, take her out for a Tennessee tune-up and run it a little harder to get the pressure up and heat up/circulate the good cleaning detergents.
If it doesn't quiet down from idling, a slower gradual drive may help. I've done it both ways.
Based on what I can hear on your video, I would assume its a collapsed lifer. A lifter that won't pump up is different than one that is jammed in the actuated position for AFM, or cocked sideways like I've seen on some YouTube videos.