Nailisi naturally had her own thoughts about who was closer to her. She left the snake egg behind and gave it to Sika, but Sika had no use for such things.
Saleen had no idea that Nailisi kept snake eggs, which were even more precious. At the moment, he simply focused on the red rock egg's shell.
The shell of that egg was hard and hot. As such, no conventional weapon would be able to cut it open. In fact, it would even be considered a very powerful piece of magic equipment on its own, at least when it was used for protection.
Saleen could not afford to leave the shell behind. Van Gogh would escape if he did not end up taking it away, and members of the Tribunal would return and find ways to pick the place clean.