Other mistake: After Linx plants his flag in the ground claiming Earth, Irongron and Bloodaxe look offscreen for no reason, as though the shot is finished.
Invasion of the Dinosaurs - S11-E2
Other mistake: The Tyrannosaurus rex which appears in this story does not actually roar; instead it says the word 'roar' several times. There may be little scientific evidence as to what sound a T. Rex made, but it is unlikely that any of them spoke fluent English.
Answer: It was never destroyed on-screen; it was intact at the end of the TV movie, and destroyed by the start of the 2005 series. It was destroyed in the novel "The Ancestor Cell," but in a completely different manner to what happened in the series.
DaveJB