Can Hephasto spawn with Conviction in NM?

Ive done over 100 runs of the river of flame on Nightmare and have not been able to bind a Hephasto with Conviction. Can anyone confirm either my bad luck or that it's not possible until Hell? Maybe Blizzard patched it out. It is pretty busted to be fair. Thanks in advance for any support! :)

I also play on /players8

Im a relatively newer player. I beat hell on the original once and once on Ressurected.

I got it! I was binding everytime just for the giggles. I stopped binding and got it in 3 runs. Maybe that affects it maybe my luck finally rolled right ¯\_(ツ)_/¯