That is not a cheater bar, but the synchronize bar, it keeps both side moving together. The missing bolt is a shear bolt, grade 5, nothing harder. It is there to break in case the slide gets in a bind. It keeps from destroying more critical components. Most of those are 1/4 inch in diameter, (14x20), and about 1 and 3/4 inch long. Make sure and get a nylon locking nut to put on it, and you will need 2, 7/16 wrenches to tighten. Just sung enough so it doesn't rattle. Better get a couple of bolts, in case there is a problem you don't yet know about. Since your camper is an 04 model, not unusual for them to just wear out after several years.
Also you will have to move one side or the other to bet lined up with the holes. Just count the teeth, and make sure you get on the same one, else the slide will be crooked.
2012 Ford F250 ext. Cab 4x4
2002 Jeep Wrangler Sahara
2008 Yamaha V-Star 650 Classic
2008 Work and Play 18LT