Try to unpack with dsg.
Edit
With 4x4:lzma it works
Code:
19:50:13 - Overall input size: 48.25 GB
19:50:13 - Overall output size: 40.11 GB (Ratio 83.14%)
19:50:13 - Overall conversion time: 03:11:26
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19:50:18 - Starting Data1a-01.bin archive decompression.
20:22:23 - Starting Data1b-01.bin archive decompression.
20:23:16 - Overall decompression time: 00:32:57
20:23:16 - All files have been successfully extracted!