@Colin_Minihan -- welcome to this peer-to-peer discussion forum, where volunteers try to help.
This forum is not a direct path to Shaw Support (1-888-472-2222).
One way to proceed is to contact Shaw Support, to see if another ID can be added to your account.
Another way is to give them the ID & password to your My Shaw Portal. Then, they can logon and click on "Pay Bill". Of course, you need to have 100% confidence in them to do nothing more than clicking "Pay Bill", i.e., not to change the password to the ID, nor to delete your E-mail ID, nor to change any services.
Or, setup "direct debit" with your bank, so that you/they do not need to do anything -- the Shaw invoice will automatically be paid on the due date, even after you die.