Not true for Apollo 7, there is a padloaded threshold at which the mark is accepted automatically or if the N49 should be displayed. That is set to -1 for position and velocity threshold, which means that for Apollo 7 every mark will show the N49, even if the mark has near zero DR and DV.
I think what actually is going on in that second scenario you posted is that you are on the final pass through P34. The normal workflow with P34 is that you start the program, give it a bunch of inputs and then when you get to the N45 display you can choose to do marks, or recycle the program with V32E or start the final pass through with PRO. On the final pass the program doesn't allow any marks to be made anymore. So you probably did the PRO on the N45 prematurely, instead of a V32. You can actually see if you are in the final pass through P34 in register 3 of N45. There are three things it can show:
-00001: for other than final pass
-00002: for final pass with IMU not aligned (I guess this is a bit unlikely to get)
+XXX.XX DEG: Middle gimbal angle (yaw) of the TPI maneuver (final pass and IMU aligned).
For you it shows +00267, which means you are in the final pass and the TPI maneuver will have a yaw angle of 2.67° (I think this is so that you know that the maneuver can be made with the current alignment and won't go into gimbal lock).
I think the only way to resolve this is to go to P00 and then start P20 and P34 again.