He could have been fleet saving and not attacking. Death Stars are used more for FSs than attacking.

fleet saving with just 5 deathstars alone? with the deathstars heading for a planet with my fleet on it? while he has more resources on his planet then he can move should he have to?

Yep. It's called a deploy fleet save. It's recalled mid-flight.

it was recalled after 5 minutes and it was traveling at full speed and all his stuff was still at his planet

Then it sounds like he ham handed the coordinates and recalled when he realized his mistake.