I think the bug is in toolame.dll.
I've tried it with avi2dvd's ac3 output (in stream demux) to mp2 AND in a direct from vob conversion to mp2.
The bug goes away in besweet when you tell it to use mp2enc.dll instead of toolame.dll (the command are the same).
Try
"D:\ForCd_DvdTools_Mar04\Audio Tools\BeSweet 15b26\BeSweet.exe" -core( -input "E:\Movie\ep1 AC3 T01 2_0ch 192Kbps DELAY 0ms.ac3" -output "E:\Movie\ep1.mp2" ) -azid( -s stereo -c normal -L -3db ) -ota( -hybridgain ) -mp2enc( -m s -b 12
or
"D:\ForCd_DvdTools_Mar04\Audio Tools\BeSweet 15b26\BeSweet.exe" -core( -input "E:\Movie\VIDEO_TS\VTS_02_1.VOB" -output "E:\Movie\Ep2.mp2" ) -azid( -s stereo -c normal -L -3db ) -ota( -hybridgain ) -mp2enc( -m s -b 12
Your paths to the programs instead of mine, of course...
<edit> Oh, this was from an episodic dvd too, you'll have to join the mp2 from single movie vob's (copy /b vob1.mp2 + vob2.mp2 + vob3.mp2 final.mp2).