Is the kids session void now that Jane is dead, or can the still succeed? Are the time and space tiers need for the whole game?

I assume you’re talking about Jade, but yes they can still win.  They really only need the Space players’s planet since it’s always Land of ??? and Frogs. She already made the frog anyway.  It has just been sitting in a bubble on the bottom of a volcano for three years.  I’m sure it’s fine.