It can be an MEL item on some aircraft (see) Operation of Wide Body Jets with Door/Slide Inoperative. I'm not aware of single aisle aircraft (e.g. B737, etc.), except for cargo-only configurations, providing MEL relief for inoperative door slides.
If it's not an item that can be deferred per the MEL for a particular aircraft it's likely going to take at least an hour (probably much more depending on the circumstances, type of airplane, etc.) to repack/replace the slide, do the paperwork, reboard the passengers, etc., even if the aircraft is at a company maintenance base airport with the necessary maintenance personnel and equipment. If the aircraft is at a non-maintenance base it would be hard to image resolving the issue in an hour.
Can you provide a source for the report you are referring to?