Split tab-one person pays while another patron in the party doesn't realize the tab has been split.
Seriously doubt this was the case at MP.
Payment is left in cash, server doesn't realize or it gets picked up by someone else.
I don't think this happened at MP. They paid with a card on the sidewalk.
Payment is left in cash but not enough (i.e. bill is $40 and patron thought they left 2-20's but they left a 20 and a 10).
They paid with a card.
Or in this case, a restaurant charges 18% gratuity. Patron leaves just enough money to cover the tab, refusing to pay the gratuity, then the bill isn't completely paid.
If the bill isn't completely paid, it's Dine and Dash. And if they didn't like the food and punished the waitress for it, that's lousy.
I don't know, and nobody knows all the details. I'm just going to say that IF it was leaving without paying, for any reason, it's Dine and Dash. And I don't understand all the twisting into a pretzel to somehow justify it. Sure, the examples you gave are possible, but IMO, not probable in this case. MOO.