On the face of it, I do not see a real difference between the two phrases you cite - document change request vs. document control change request. To whoever created this process and associated forms the reason behind the two functions must have been readily apparent. Your DCR Log records a number for the DCR that is also the same number recorded for the DCCR. The DCCR Details does show a difference between some of the DCCR's and DCR's listed in that document. Why they would not align as in the first document, who knows ??? The final document is called a Document Change Request, parenthetically DCCR No which only adds more confusion and less clarity.
There is a difference, but perhaps it is a difference without a real distinction.
Document control requires us to fashion a system for the registration, tracking, usage and disposal of documents throughout their life cycle. A form to request a change is a logical outgrowth of that process. The larger the company, the greater the need for documenting requests for change so that they do not become lost or forgotten. Sometimes in our zeal we create additional bureaucratic burdens for ourselves and co-workers that do not stand the test of time and objective scrutiny. Sharing drafts of new items helps weed out the redundant from the necessary.
We have a document control policy and SOP which includes a document register and document change request form. We do not use an additional document control change request form - sounds to me like more wording for the same thing.
Maybe a document control expert can help us figure this one out. Good luck!