Its not much of a plot hole . Basically, the dialogue you used for Vader and Trakin was taken after her interogattion, which Vader specifed her resistance was "considerable". Secondly, the scene preceding Han and Leia's dialogue you posted also reveal that Tarkin and Vader had a tracking device installed on the Falcon.

Tarkin: "Are they away?"

Vader:"They just made the jump into hyperspace"

Tarkin:"I'm taking an awful risk Vader, this had better work."

"THIS HAD BETTER WORK", indicates a PLOT POINT.

So when Han tells Leia that their escape worked, she knows better, that of course the bad guys would be tracking them, and that they have to have their last stand simply because R2 has the plans and they will be delivered to the Rebels by the time the Death Star reaches them. So yeah, in a way Leia is leading the Empire to the base simply because the Rebels will have a means of stopping them.

So again, not mch of a plot hole, if you can even consider it that.