Possible to build iOS app for enterprise (in-house) distribution?

We have an AppGyver project that is an internal iOS app for our employees to use.

We could not get the build to succeed using the Apple Enterprise certificate, and had to use a public App Store certificate/identity in order for the build to succeed.

Does AppGyver support creating (building) apps for enterprise, in-house distribution? If not, has anyone figured out a good workaround, aside from all of our users using TestFlight.

I’d prefer to avoid Ad-Hoc distribution because then we have to manage it every time someone gets a new device and there’s a limit of 100 iPhones.