Violet appears as "married" aged 20 in the 1901 census, living with parents in Braddan.
It seems strange that the Registry Office would need to know the Volume to look it up as you have both names and the year.
The marriage is not in my index of marriages for that year - maybe they married off the Island.
The page number you give is strange. In the record of marriages there are two marriages recorded on each page of the Volume.
Strictly for my own purposes when compiling my index I append 'a' to the page number to designate the first fully identified marriage on the page.
The Braddan page numbers are not in the 800s for 1900.