There's no reason to cut it up. I do cut up boneless meals when they get down to the last bit about the size of my fist because I know that she gets lazy with the last bit of boneless meals and doesn't chew it, but other than it's fine to leave food whole. When first feeding raw they don't think that it's their daily food and eat with gusto. I know with Crouton she ate like I was going to take it away at first but then as I continued feeding it and she knew it was a forever thing she calmed down a bit and now eats normally.
Couple of questions, how much food are you are you giving them? Is it appropriate for their body weight? (ex.2%-2.5%) Sometimes they will regurgitate food if they eat too fast (which sounds like Miko is doing) and it is not sitting well in their stomachs, it's really not a big deal. A lot of raw feeders I know including me will just let their dogs eat it back up again (no need to waste expensive food) then they re-chew the food and it stays in the stomach, if you're open to them eating throw up

. I was watching my sister's dog and Crouton regurgitated her whole prey lamb into two neat even piles and before I could do anything about it they each ran for a pile and ate it up, each keeping an eye out for the other, lest their pile of vomit gets stolen. That time since she was eating a whole prey lamb I think she just ate too much. You would think by their teeth showing that the regurgitated lamb was like gold! But regurgitation is a natural thing and I would just let them re-chew and eat it back up, at first Crouton was weird about eating it back up because she thought she did a bad thing (based on my grossed out expressions, which I changed) and now she sometimes throws up because it's not sitting right and she eats it back and I just have to deal with clean up. But regurgitating only happened with us in the beginning because she was too excited about her food and ate really fast.
It was easier for me to start out raw feeding with bone in chicken breasts because the bone % is less than drumsticks or leg quarters and it might be easier on the stomach. Also you can feed their food partially frozen and that will slow them down a lot. That's great that you're not getting poop issues, give thanks for the little things