multiple bags for 10g batch?

Gonna brew my first 10g batch tomorrow. I usually brew 5g biab in either a 13g or 15g keggle.

I've got roughly 21lbs of grain that I need to mash but it doesn't fit in my usual grain bag. Can I split the grains b/w two bags and place them in the same keggle? I understand that I don't want the grain to be compacted and the keggle should have enough space to hold everything, it's just the bags I'm concerned with.

I recently acquired a bazooka screen that only fits my 13g keggle for the time being. I'd thought about just using that and the keggle as a mash tun and forego the bags entirely...but I've never really sparged (except dunking). I'd imagine the bazooka screen would act as well as a false bottom and I could drain the mt into the 15g keggle & boil there.

Thoughts? Advice?

The first time I tried BIAB I used 3 paint strainer bags in a keggle for a 10gal batch, that worked just fine, no problems. I dunk sparged in my fermenter bucket, that also worked just fine. Multiple bags are kind of a pain to deal with but will work until you get a better bag solution. I did stir each bag a couple of times during the mash. I also turned on the burner a couple of times for a couple of minutes just to keep the heat up, it didn't affect the bags at all.

Good Luck.