Charting

Just a question and didn't see another topic on this. At work the other night I received report on a patient that was just admitted 1730 and I come in at 1900 the nurse was still working on the admission paperwork. About 1940 she handed me the chart and left. I did my assessmnet on the patient and noticed that the nurse wrote at 1800 'see admission assessment'. I looked at the admission sheet and the first 2 pages were done, page 3 the assessment part was blank and then the back page was done. I told my charge nurse about it and he said to fill it out. I stated since it was timed 1730 and I was not there that I couldn't. Of course I was written up for 'disobeying the charge nurse' I don't feel that I was wrong in not filling it out. Any suggestions?