Without getting into a debate about the existence or non-existence of soul, we have to think about what Dick was trying to say.
The Replicants certainly showed evidence of emotion, but that doesn't, necessarily, mean soul. Perhaps evidence of soul is the ability to show mercy, so in that case, the character played by Rutger Hauer, showed mercy when in his dying moments he caught Deckard.
And what about the woman/Replicant, the one that didn't know, and even Deckard, there is some thought that he also is a Replicant, is his behavior evidence of soul?
Sorry I can't remember the names, it's been a long time since I saw, Blade Runner, or read DADofES.
Perhaps one of the things that Dick was trying to say was, if you build machines that look and behave like humans, they also will develop emotions and a soul?