Haye would've smashed Joshua to bits. As soon as he wobbled he would have been all over him as we've seen and Joshua would be in a state like Enzo, Barrett, Ruiz et al. Not to mention that Haye has far more power than Whyte and way better fitness, yet Joshua was wobbling and wishing he could borrow one of Ji Sung Park's lungs.
Only issue with Haye beating Joshua is the shoulder op and January, we'll see how he does and if its still there. Fury would toy with Joshua and laugh at him doing it, not to mention break him mentally in the pressers.
Joshuas been good to watch, its been a good ride and adds to the Fury, Haye, Klit etc drama but he's way off at the minute, that last fighter he fought was picked up off the street, joke fight, he basically fell over. He's basically the English Wilder.