Merlin's Magic Sleepsuit. You can put them in it even when they roll. As long as they can't roll while they are in it you're okay, and at your baby's age there is no way they can roll while in it.
Hey Haley! This is only my first baby so I don’t know how helpful I could be, but I went through a somewhat similar journey with my son. He actually NEVER liked to be swaddled haha and won’t sleep on his back so he’s a tummy sleeper with all the extra tools and gadgets to monitor his breathing. But even then he still wouldn’t sleep long. Partially because he kept rolling from belly to back and once he’s on his back, he’s up! Long story short, we started doing what you guys are planning on doing, the dreamland swaddle/sleepsack with the buttons undone to let his arms out, and now he sleeps 5-7 hrs at night, and the rolling over is to a minimum. I hope that helps!
@Alyssa I appreciate the advice but a friend of mine, her baby over heated in the Merlin sleep suit. With the AC on and a overhead ceiling fan. She was found and rushed to the hospital just in time. Drs said if they were 10 minutes late she would have passed so I will not be buying or using this suit