No. You said that the Afghan suspects must have signed the Geneva convention in order to have those rights apply to them. By the same logic you should have to sign a copy of the Charter in order for it to apply to you.
The Charter applies to the Canadian government and how it deals with Canadian citizens, because it is signed into law by the Canadian government. The Geneva convention applies to the Canadian government and how its military personnel behave in the field because it is recognized and signed into military law by the Canadian government, according to the convention.
Likewise, Canada is also a signatory to the ICC, which is probably more pertinent, anyway.
And by the way: Welcome back.