yes, contact with the platform is considered transitive as you’ve noticed in the manual.
What the q&a is referring to is a goal that is scored in an alliance’s home zone, not balanced on the platform. As of now, goals need to be directly contacting an alliance’s home zone (the tiles, tape lines, or the platform structure) to be counted as scored in that alliance’s home zone.
However, I believe this definition will change:
in the next manual update.