ZDP-189 can pit, but I have read it also may depend on the temper (how susceptible it is to corrosion). Not sure if this is true or not.
I have no first-hand experience with the Rockstead ZDP-189, but I do have a few Spydercos with it that I use often and enjoy quite a bit.
Recently, I have purposely used and abused an old Stretch CF/ZDP-189 just to see how much it would take before corroding (after seeing many people posting up being worried about it). Everything from tomatos & fruit, to stirring lots of coffee and soaking in various types of vinegar - all without cleaning off and leaving overnight... I didn't get much more than a slight darkening. I do have a Delica ZDP-189 that I purchased used that has a few tiny pits, but not sure what previous owner did to produce them. Also, I suspect the temper may have been different between the batches used for my older Stretch and the newer Delica.
The patina now on my Stretch also seems to be further protecting it from any further staining since it shakes everything off that I throw at it.
Overall, in my experience, if you care for the blade like any responsible knife user should, even with a little bit of delayed care, you shouldn't see serious problems.
Search on here for a Spyderco Stretch ZDP-189 (in blue) review, and you'll see that users fairly unbiased experience. His stainless liners rusted after swimming in the ocean, before the ZDP-189 saw much corrosion or serious staining.
VG10 clad ZDP-189 sounds like a dream!