I watched the last two minutes or so again (not sure why I put myself through it) and 2 cowboys players were two metres offside when they tackled Parker on the play before Milford made the break. Milford also broke through two tacklers so I think that means Kyle Feldt stripped him in a two-on-one tackle by the rules even though it was one-on-one at the time (not 100% sure on this).
The Broncos were duddued but, and I say this as a hugely devout and still bitterly disappointed Broncos member, they have only themselves to blame for playing negative football for the entire second half. Even though they only came up 5 seconds short, they should have been playing attacking football for at least the first 15-20 minutes of the second half. Defending a 4 point lead for 35 minutes against the cowboys is ridiculous.