I think the worst that can happen is a round will fire, bolt goes back, recoil tube dislodges, your buttstock comes off with a bit of force. I don’t think there is any real danger other than that, the bolt can’t exit the rear of the receiver it will just impact the back of the receiver and will be contained.
if this were to occur I think you’d have warning signs, such as a slightly loose recoil tube before it happens.
I’m glad you got it sorted out! Sounds like it will work just fine as you felt the torque of the nut was sufficient.