That disc was damaged in a previous failed burn, and that's why you're getting different error messages with it (e.g. the number I quoted above should always be 4,173,824 for blank DVD+R DL discs).
You see, the burn process relies on the burner/firmware/media combination: since you're using the latest firmware for your burner, the next easy thing to change is media. The software can't force the hardware to do anything it doesn't want/support.
We know from our own tests that Verbatim 2.4x blanks work on most burners, even when many other dual-layers failed. If you don't want to take our word for it, fine, but look around on the several forums that deal with burning/games/etc and you'll see the consensus.
If you're going to get a new burner have a look over at cdfreaks forums, they test a lot of drives and there you'll find which brand/models of burner might be able to burn your discs.