Hi Hector,

You have to override "report_saleorder_document" template for this customisation.

Where,  you can add the logged user name by adding "doc.user_id.name" inside your specified div. And I think, Quotation name in report is "doc.name". If you want to change it,  just go and change sequence or settings->sequence & identifiers and change it or you can give a customised Char field reference in report.