[mothered]

when I recalled they told me they said they could give me a refund and would start an investigation with canada post (which i assume is protocol),

If this Is stated chronologically, It doesn't make sense.

I don't see how a refund can be Issued, and an Investigation take place thereafter.

but the email I received only stated "Your Case has been received" instead of a refund confirmation.

I'd say they've opened an Investigation.

Please keep us updated as developments come to hand.