Can a creditor and the collection agency who purchases your account from the creditor both report the same debt in separate instances to a CRA?

Yes, they can and it's customary for them to. The original account should have all the history, including late payments you made and the status (collection or charge off), the DLA, and date the account was opened. It should not be showing a balance due once sold or assigned to a collection agency. It may have a statement about being sold or transferred, but not always. The CA account should have the date they received, or were assigned, the account and the current balance (often with interest added in). The DLA should not have changed.