Neither would, in my opinion, be the best course. You can send a DV, but it most likely would not be timely, and even if timely, does not compel them to prove their determination of accuracy. You need a court to compel that.
I assume the debt collector sent dunning notice at the time of reporting to the CRA. If so, any DV would be untimely, and thus place no restrictions on the debt collector.
The issue appears to be a contest over whether the debt was satisfied. CR exclusion does not cancel the debt. While it precludes one from discovering the old collection by a simple pull of your CR, you still have an assertion of unpaid, delinquent debt.
If you have disputed and they have verified, you could still send a direct dispute to them, but any direct dispute can be dismissed under the rules without investigation if substantially the same as a prior dispute, including one filed through a CRA. Even if they did investigate, they dont have to "prove" the issue in order to verify.
Compelling them to produce evidence and get the matter resolved in a binding manner will most likely require you to bring civil action.
