I think a fair answer to this is “we don’t know”.
I’m not aware of anyone using 16 screens end to end like that.
We had a similar enquiry a while ago, and I was looking at the latest nVidia mosaic software that goes with the NVS810 cards, which is designed for that kind of application, and my recollection is that it tops out at around 20,000 pixels on any axis.
Sorry I can’t give you a more concrete answer. There are people on here using 16 screens in a more standard video wall configuration and they may be able to offer you some insight if they see this.