Bonding process..what happens at night?

I want to start the bonding process again with Poppy & Scratch probably next weekend. I'm thinking of setting their bonding area in our bedroom but I'm not sure what to do at night. The only thing I have to contain them with is Poppy's pen which I was going to wash down with vinegar first, then place it on a layer of newspaper with an old sheet on top. I was wondering about what happens at night because Poppy can lift the edge of the pen up when she's in a huff and what else do I need to put in the pen with them? The pens around 3ft x 3ft although I can configure it to be more of an oblong shape if it was up against the wall. Last time they just kept running in circles with Scratch pullling tufts out of Poppy so eventually she didn't want him anywhere near her!

well i sleep with the buns when im bonding them so i can keep an eye on them first night i sta y awake..2nd night i sleep kepping an ear out dependant on how its progressing. could cou use string tied to the pen and tie that to a brick to eight it down? like guy rops/pegs on a tent?

I try to bond early morning, but I don't always. If they are ok - I would be quite happy leaving them all night. I would check them at midnight last thing before bed & again when I get up at 6am ish.

Every bonding injury I've had though has been done in front of me, very early on at introduction/re-introduction.

Do you think I should keep it at 3' x 3' or is that too small? Also, what do I do if Scratch just keeps chasing Poppy again? Should I just let things take their course, seperate them or try 'stressing'? I know they say not to separate them but we went 9 hours before and it just didn't progress from chasing. Poppy had so much fur pulled and had been chased so much she was completely worn out..it was really horrible to watch.