The text messages went out a long time ago. I received the voicemail notice today because I've been outside of Koodo coverage for a few months.
If you dial into your voicemail, from your Koodo phone only, you get to re-set with a new password and listen to your recent messages. Later in the recorded options, you are offered an option to retrieve older messages. Can't vouch that it works/doesn't work because I didn't bother since there would have been nothing of interest.