Written explanations are required if any required document is not available to be submitted with the application to CIC. I am sure your consultant didn't submit any written explanation to justify the unavailability of reference letters in CIC format because he understands that this is OK. But still, I think your case is not that much weak what you are considering at the moment. As you have submitted all available proofs, just pray that the VO can easily relate them to each job experience as they supposed to be. If VO becomes satisfied from the documents you submitted that you have really worked in the applied NOC, he will accept your case, I believe.
Bhaumick said:yes. all of the above... i have also attached income tax deduction statement from the employers, interview call letters too...