[GaryVoshol]

Rules <G18> to <G25> apply only to the End Game. That includes the box explaining <G24>.

Pinning <G50> is in the Robot-to-Robot interaction rules section; it applies the entire match.

The only thing that could vaguely apply here is the "strategy aimed at ... entanglement" in <G48>, and then only if you consider the game piece to be an extension of the robot. The use of game pieces in <G23> and <G24> do not necessarily consider them to be extensions of the robot. Those rules also prohibit interference by thrown game pieces. Since <G48> is a robot-to-robot rule, it would not cover thrown pieces - good luck throwing them that far.

I would consider this to be a legal (although not fair) strategy, unless the GDC changes a rule or gives a Q&A response that basically says, "No, you can't do it; the rules say so."