there were certain things that appeared in prerelease material that ended up having absolutely nothing to do with what ended up being in the actual film...
one being this thing about liz being "reclusive" or not having "left collinwood in ten years". nothing that actually took place within the narrative even hinted at that.
...
... so somewhere along the lines this was taken out of the scripts entirely.
Yes, that's quite possible, similar to how the years for the prologue as it takes place in the film were completely changed from what we were told in the WB May 2011 Press Release.
Though there could be a slight possibility that any and all hints to Liz' secret (because, remember, all the characters were supposed to have secrets) ended up on the cutting room floor for one reason or another. In particular there may have been scenes before Barnabas' arrival or soon after his arrival that dealt with much of it before Barnabas' plan to restore the family's fortunes was executed. Though, of course, probably one of the only ways we'll ever really know is if one day we get to read the script.
And speaking of scenes that may have ended up on the cutting room floor, though storylinewise it may not seem so, there is something that leads me to believe that quite possibly Vicki and Barnabas may not have arrived at Collinwood on the same day, or at least what appears to be the same day as the film would seem to imply. But more on that soon after next month's quotes/captures begin. Though the eagle-eyed among us may spot some of the evidence before this month ends.