This is easy to answer. And I think Brands had a similar thought as he nearly threw the brick but the refs did a video review. (Also, Jim Gibbons pretty much said the same thing on the broadcast (how can he be in neutral danger zone without getting near fall?), though after the video review, in typical Gibbons manner, he said the ref was in the best position on the mat to see the angle, so it was unlikely that he would overturn his call based on the video.)
Rule 4. Scoring Meets and Matches
Section 2. Takedowns
Art. 3. Neutral Danger Zone Takedown. When in the neutral position, the referee shall announce a neutral danger signal (NDS) anytime a wrestler exposes their shoulders to the mat at any angle less than 90 degrees (neutral danger zone). The danger zone utilizes near fall criteria outlined in Rule 4.5.1, but replaces 45 degrees with any angle less than 90 degrees. The NDS announcement shall occur anytime a wrestler is voluntarily or involuntarily in the neutral danger zone, beyond reaction time, and will continue until the wrestler is out of the danger zone or a takedown is awarded.
Art. 4. Neutral Danger Signal. The NDS is a verbal announcement of the word "danger," followed by a verbal three count. Whenever possible, the referee also should include a visual indication of the count. If the referee reaches the third count and the wrestler is still in the danger zone, the opposing wrestler is awarded a takedown.
Same Rule
Section 5. Near Fall
Art. 1. Near Fall Criteria. A near fall is a position in which the offensive wrestler has the opponent in a controlled pinning situation in which any one of the following three criteria are met:
a. The defensive wrestler is held in a high bride or on both elbows;
b. Any part of one shoulder or scapula, or the head is touching the mat and the other shoulder or scapula is held at an angle of 45 degrees or less to the mat; or
c. Any part of both shoulders or both scapulae are held within four inches of the mat.
So Neutral Danger Zone kicks in when the wrestlers are in the neutral position, and one wrestler's back is exposed to the mat at an angle of less than 90 degrees. If the wrestler whose back is exposed is in this position for 3 seconds, then a TD is awarded.
A wrestler whose back is exposed to the mat when in neutral such that the Neutral Danger Zone criteria are enforced can have their back exposed anywhere from 89.9 degrees to 45.1 degrees and it's a TD, but no NF should be awarded. If while they are in Neutral Danger Zone criteria the back is exposed anywhere from 45 degrees or less, then after the TD is awarded then swipes should also be given, with the potential that the top wrestler can get 2 NF or 4 NF points, if they hold the position long enough to get those points.