can someone please help answer my questions on the above as I keep getting conflicting information.

I recently gave birth to my second child and suffered a four finger seperation to my stomach muscles, from doing the core exercises recomended by my physio I have now got this down to 2 fingers. I have lost my pregnancy weight but still have a mishappen stomach. My belly button pops out, and I have what looks like a sunken hole in the middle of my tummy and the sides are all raised. And I have the following questions:

Is it possible for me to fully close the gap without having surgery?

I was told not to do anything like stomach crunches untill I got it to 2 fingers, otherwise I risk pulling the muscles further apart, now I have got to 2 fingers wont doing crunches still pull them apart, or prevent them fully closing?

Also I was wondered if tight lace corseting might help bring my muscles back together permanently, or would this do more harm than good.

Thank you for any help you can give.