"With the Bifrost gone, how much dark energy did the Allfather have to muster to conjure you here, your precious Earth?"
Notice how that line is phrased. It isn't an explanation it's a question.
Loki theorised that Odin sent Thor back and asked Thor to confirm that but he never did, nor did Thor ever state how he was sent to Earth later on
It would be like Catwoman asking Batman "How many of Banes guards did you have to bribe to smuggle you back to Gotham?"
Just because Loki asked Thor how he got back with his own theory doesn't mean that his theory is anywhere close to correct, all it means is Loki made a guess, asked Thor if that guess was right and got left hanging.
Same if Catwoman asked any of those questions above and Bruce didn't respond doesn't mean she's right, just that that is what she thinks happened