I don't know what a CO2 is but am guessing that this is a gizmo to take a digital feed from the SBM-1 and convert it to optical so the JB3 can recieve the digital feed. Based on that assumtion: Two people each taking a digital feed from a SBM-1 - one records on a D8 and the other on a JB3. There is abolutely no difference between the two sources - the D8 and the JB3 at this point are just transfering the bits to their particular recording medium (tape in the case of the D8, HD in the case of the JB3). For this person to think one could have richer bass or sounder clearer is nonsense and shows they aren't very clear on the concept. I suppose the transfer methods of each could yield different results but if each person transfered the source digitally and no processing such as EQ, normalizing or similar editing occurred then the resultant transfered sources should be the same as well (other then any differences in in tracking/indexing).
As for who should get credit on the text file...you two can scap it out over that one - seems a bit trivial to me. If I were the patcher and doing the text file, I'd at least make a note thanking you for the patch and/or explaining that I patched out of your rig. Ultimately the idea is that folks can track down the source person/people if there is a problem discovered, questions etc. I also think it is always couteous to give credit where it is due.