Ok I posted this in another thread where I thought it fit, but was told that it took the discussion off topic. So I refined it a little and here it is below.
Our situation was that red had a stack in the alliance goal (non-protected). As they were backing off in the last 5 seconds the blue robot started pushing them back into the stack as to de-score the stack by having them touch it(bottom cube). After it was over with, the other ref and I discussed it and looked in the rules. In SG3 it looks that it might be covered, but we were still unsure. SG3 B? It potentially would have de-scored the whole stack of more than 6 cubes after the bell ended the match
We were on the fence and went on the side of offense getting the benefit of the doubt and did not call it.
SG3: Stay away from your opponent’s protected areas. Robots may not intentionally or accidentally, directly or indirectly, perform the following actions:
B: Contact any Scored Cubes in either of opposing Alliance’s Goal Zones.
This is one of the cases that is not an automatic DQ, but can be if it is match affecting.
You question was indirectly answered in the Q & A post below. The example talks about knocking over a stack however forcing an opposing robot to touch their cubes nets the same result.
To answer your specific question, a Blue Robot pushing a Red Robot such that the push “knocks over their stack” and causes Cubes to become de-Scored would be considered a violation of SG3 part F on the Blue Robot, and should result in a Disqualification.
To directly answer your question, if the red bot was no longer touching the stack and blue pushed red back into the stack, that should be a DQ on blue. That violates rule SG3 case f. The stack is no longer scored because of the blue robot, therefore they blue should be DQed.
Since this didn’t happen in the protected zone and because the blue robot didn’t touch the cubes SG3
A-G don’t apply. As long as the blue robot never damaged the red robot or trap them for 5 seconds this would be just a be a clever team that found a small hole through the rules in order to give themselves a slight advantage. BUT the red robot could possibly combat this with G3 if they wanted to reason that it is implied that SG3 B means any indirect AND direct contact not just contact by the robot.
The rule states that a robot cannot cause scored cubes to become de-scored either directly or indirectly, intentionally or unintentionally. A blue robot pushing a red robot into a stack just to touch them and cause them to be de-scored is no different than pushing the red robot into the stack and having the stack fall. There is no loophole. The only difference between the non-protected zone and the protected zone in this case, is that this violation in the protected zone is an automatic DQ and in the non-protected zone is only a DQ if match effecting.