Cannot configure valid signing cert for enterprise distribution

I'm a comple iOS noob and I've inherited an iOS application from a recently-resigned employee and am having to build it for enterprise distribution. I'm running into problems getting a certificate with a valid public/private key pair. We use an on-premise instance of an MDM tool for enterprise distribution, not the Apple store, so I need to sign my app for enterprise distribution. I do have the luxury of having the MacBookPro that was used to develop the application, but the Apple ID used to build it belonged to the previous employee, so I have to build it with our team's Apple ID. I'm building with Xcode v6.3.2 on Yosemite v10.10.3. It seems like the root of my problem (aside from the fact that I don't know what I'm doing) is that I'm building with a cert that does not have a public/private key pair (at least what I can gather from this post).


I'm logged onto the MBP as the former employee, and when I first build I get this message:

1)


I added our team Apple ID in Acode > Preferences > Accounts, and when I then try building I get this message (name of component changes with each build attempt):

2)


If I click the 'Fix Issue' button then I repeatedly get image 1).

>>> How/where do I change the Apple Id associated with this application??


When I go back into Preferences > Accounts and view the iOS Agent details and attempt to add the Signing Identiy for 'iOS Distribution':


... I get the following message (which led me to the post referenced above):


I visited the member center and downloaded one of our team certs and installed it on the machine, but when I view it in the Keychain Access window, there is no public/private key pair as the post said was required:


I can't seem to get past this issue. Any recommendations would be greatly appreciated.


Thanks in advance.

My HTML image tags didn't work for some reason. Here are the URLs to the 5 images noted:


http://giswebtest.bellevuewa.gov/images/ios_1.png

http://giswebtest.bellevuewa.gov/images/ios_2.png

http://giswebtest.bellevuewa.gov/images/ios_3.png

http://giswebtest.bellevuewa.gov/images/ios_4.png

http://giswebtest.bellevuewa.gov/images/ios_5.png

Cannot configure valid signing cert for enterprise distribution
 
 
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