I doubt this will work for you*, but please report back and tell us how things worked out.
(* Because you also need their certificate, which is per-team. In theory you could make your own certificate, but that wouldn't match the certificate used for generating the provisioning file. Would love feedback if I'm wrong.)
It will not work without a certificate. Even with the certificate, it might fail when signed with B4i, but this can be solved by opening the generated project with Xcode.
Could you help me figure out what I need to do in Xcode? If it's not too complicated, I'd like to continue developing with b4i.
Do I need to change the package name in Xcode and add the credentials?
First, I'd like to compile with my account credentials and see that it works on my phone. I tried uploading the .p12 file to the keychain, but it says the password is incorrect.
Thanks
Start with the simulator. Compile the app in release mode, targeting the simulator and then run it from Xcode.
The next step is to create a device build in release mode. Let Xcode update the recommended project settings and try to configure the certificate + provision profile. It is not trivial.