Very elementary question for developers...

Greetings ---

Perhaps someone here will know the answer to this question (frustrating problem grrr! )

I will attempt to outline this very simply so as to provide the clearest possible description of my problem. Here goes...

- Have outsourced a developer to code an app for me.

- Code is completed.

- Developer is at the stage where he is attempting to load the app onto iTunes for the approval process

- Developer is saying, "I can't do it because I don't have the Distribution Certificate."

- Developer is saying, "The only person who can give me this certificate is the last developer that has uploaded an app for you."

Now... here are further details:

- I have lost contact with that last developer, so I don't know how to get this man the certificate that he needs.

- Maybe it's unrelated, but the screen-shot below lists two names: 1, my name (or, my boss' name, in reality) - and just below, the name of the last person who uploaded an app for us. *NOT* the person attempting to do so, now.


Finally, this:

I have given this developer all login names and passwords, etc. so he may login to my companies iTunes Connect/Developer Portal, etc. So I am left wondering if perhaps the reason he is not able to obtain said Distribution Certificate, is because he is not listed as a "user" in the attached screen shot. Should I list him?

Any angles of advice are immensely, immensely appreciated.

*PS- Before advising me to "read the manual," I will let you know that I, personally, am merely handling a job for my boss. I know nothing about coding.