Chad LaMar Alvord

Chosen answer: They likely thought that they'd be able to defeat him without having to make sure he didn't escape. Easily explained character mistakes all around.

Captain Defenestrator

Answer: Initially, they never anticipated he'd escape, so they didn't think to slash or damage his ship in any way. He had to resort to trickery to get away, so Yoda could save Anakin and Obi-Wan. He simply took his opportunity then to get on it and leave Geonosis.