The link didn't work for me but most of the small screens I have all just pull inward. They're pretty much held in place by friction. They don't have clips or anything like that holding them in place.
You may also consider just using a vacuum cleaner with an upholstery attachment.
Jeff & Laurie -- Full timing in Rockport, Texas
Auggie (our beer-loving English Cocker Spaniel)
Angus (55 pounds of attitude in a 5 pound chihuahua body)
Our home base -- 2018 Grand Design Solitude 375RES -- The "Uno Mas!"
The mobile office -- 2016 Crossroads Hill Country HCT26RB -- The "Poquito Mas!"
Gone but not forgotten: 2015 Heartland Landmark 365 Key West (lost to Hurricane Harvey)