Pain in the ass cleaning my labs bed

I have an 11 yr old black lab and recently bought her a fairly expensive orthopedic bed to help with her arthritis. The cover is sort of like a canvas material that’s a little slick, probably due to a water resistant treatment. I wanted to clean the removable cover after a couple of months and it had a lot of hair on it. I didn’t want to put it in the washer with all that hair on it so I tried to remove the hair with various methods but only about 75% of the hair was removed. I tried vacuuming, using a sticky lint roller, packaging tape and duct tape wrapped around my fingers, and an air hose with a fine tipped nozzle on the end. I think the lint roller worked best but it would taken a very long time and probably more than one refill to remove it all. I ended up washing it with 25% of the hair still on it and had to spend time wiping out the washing machine tub when I was done. OMG, what a pain! What do you guys use, or do you have any suggestions?