You can do it in any cast iron pan. I didn’t do it for these breads because dough with more whole grain is less likely to have crust bubbles anyway.
Try one maybe two ice cubes max under parchment just before putting the lid on.
It is safer to have the parchment barrier between the dough and the water. I once put ice cubes directly on some dough, then the lid, and the result was weird large bumps on the crust where the ice cubes had over moistened the dough.
In my experience, sometimes you risk with ice that the score seals prematurely because of too much moisture. I have yet to figure out the perfect sequence of actions, but I also haven’t tried super hard : ) I’d love to hear what works for you and next time I do a dough with 25% or less whole grain, I’ll do ice tests.