I am glad you have experience with it but I had rotties in the past and thought I was ready for a corso, until Hemi entered my life and showed me how wrong I was. They aren't like the rotties people have now and underestimating then can result in issues.
I fully understand how difficult it can be to have babies and puppies at the same time, I had one 18 month old and was pregnant with the second when I had my first litter. Nothing in life worth doing well is easy, but I still would not sell two together, sorry personal opinion which I know won't be popular with you.
I am also aware of who Zues is, he is a nice male and while from nice lines I don't know that I would call them old lines. I wish you all the best and hope it turns out the way you hope.