Before the contractor goes away, you should sit w/ them and go through the process of creating a new key pair and replacing the old one w/ the new one so you have him/her on hand if anything breaks (and if indeed that's the case, that the credential management in the system is a mess, then it's a huge red flag and you may want to question/verify everything the consultant did for you).

Once they're gone you should change the credentials again, but at this point there is a low risk of it not working.

Shlomo says:

Thanks for that excellent point, William. If the "simple" things don't work, why should you trust that the rest works as advertised.

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