Well to be clear, it's that the PID & IV combination doesn't match wild encounters.
For example, using the PID of your Slowbro, at a glance, I could tell that none of the IVs on it matched.
(of course, we could have used those IVs too, but there's no guarantee that PID matches the proper encounter slot etc)
It's easier to Gen mons in Gen 5 and above; don't have to worry about this kind of stuff.
No worries mate :3