Hi you don't know me but I have been reading your sad story and Just wanted to say how sorry I am for your loss,
Do what you have to do to make peace with your loss, I had a D&C last year mc at 13wks and for me I needed to know I had all the tissue from the pg removed as I have had a history of retained placenta, But saying that I would have prefered to deliver naturally if my bub was older and I could have had the chance to see and hold and say goodbye, So if you can wait it out then do so Nature does have a funny way of sorting us out for the best in the end !
My prayers are with you and your family right now and I do think you should be given more testing as this has happened twice now,