Update!! We changed the bag about 5-6 days ago and the smell is much better so far! (The smell from the prior bag and vacuuming did get a little baked into the vacuum, but it's mild.) I'm actually wondering if the cause of the issue came from my dog's nail clippings. I usually clip and file his nails weekly on the carpet and then vacuum it up. I'll be doing that on a hard floor and sweeping it up with a broom from now on.

The bad odor could have also been from the Dart sucking up anything that my shark had not been sucking up for years --some commenters presented this option.

This time around I went all out in case the smell were to get gnarly again...I added an All free and clear dryer sheet first. Waited a few days, it still seemed fine but (as suggested from the comments), I put in aquarium charcoal/carbon pellets...about 1-2 tablespoons. I checked the bag smell after vacuuming tonight and it seemed fine. No stench has grown like it did last time. I also bought Fresh Wave vacuum beads off of Amazon, so I there a small capfull off those in tonight. The looks too these 2 items are below.

Aquarium carbon: Marineland Black Diamond Premium... https://www.amazon.com/dp/B0002566WO?ref=ppx_pop_mob_ap_share

Fresh Wave vacuum beads: Fresh Wave Vacuum Odor... https://www.amazon.com/dp/B0012T551C?ref=ppx_pop_mob_ap_share