Let my preface this by saying that I believe all parallel construction should be illegal, and I hope/believe that it will eventually be ruled accordingly. Partial truths are still deceit, and dishonesty in the legal system opens it up to (further) abuse. It's either illegal to lie under oath, or it is not, and the government should hold itself to the same standard that we expect of citizens.
That said, parallel construction is precisely about concealing the impetus. The classic example is a traffic stop that appears to be random, but is actually targeting a vehicle. The targeted vehicle could well have been stopped solely for whatever reason police used, and so that's the "parallel construction," even though police knew exactly which vehicle they wanted to stop.
"You'd be told only, âBe at a certain truck stop at a certain time and look for a certain vehicle.' And so we'd alert the state police to find an excuse to stop that vehicle, and then have a drug dog search it," the agent said. http://www.reuters.com/article...
Bringing a canine unit to the storage facility would allow the officer to tell the partial truth that he got a hit on a storage unit during a walk-through, even if the impetus for bringing the dog and doing a walk-through was because of a CI (and even if the hit was prompted). The deceit isn't in saying how the contraband was actually discovered/acquired, but in what the impetus was for using that (perfectly legal) method in the first place. That part is the "parallel construction."
Now you might have been saying that GP's speculation that it was parallel construction is wrong, but we're all just speculating on what the officer might have been doing anyway. Maybe it was just a recreation for the camera and they forgot to edit that part out.