I would not send in duplicate information, it will just confuse the VSR and RVSR. I would sumbit the 21-4138 and state what dates you submitted the earlier evidence.
Also, with the evidence showing as closed, not received . The VSR " Veteran Service Rep." probably just closed them instead of marking the correctly as received with the proper date. This fact could also be rectified with the use of the 4138. It's possible if you request that the dates be updated they will do such.
Also, I currently have a claim for IBS in with the VA. It is a presumptive, but sometimes they will ask for an etiology ( exact cause). I have a lumbar condition, and one examiner tried to blame it on that. The VA sent me for another C&P examine and this DR did several EMG's to discount the lumbar cause. So, it's possible they could possibly trying to blame it on something else.
Hope this helps a little bit, if there are any further questions I'll be more than willing to try and help.