This is obscene behaviour but not surprising, the Christian message is not, as you suggest, one of "tolerance, acceptance, and inclusiveness" and it never has been.
On the contrary, as are all religions, Christianity is divisive, exclusive, authoritarian, controlling and hypocritical. It is also based on a human constructed myth.
Some of those who are religious, whether Christian or otherwise, are intelligent, sensitive, caring and compassionate people. Many, if not most, are not. What is common to all of them is that they are conditioned to believe myth and codes that are discriminatory, prejudiced and even bigoted.
The mystifying thing here is not that a 'Christian' institution has fired these two employees on grounds that do not stand up to moral scrutiny. What is mystifying is that good people such as these two actually continue to practice and possibly believe the hypocrisy and nonsense that religions, their churches and their hierarchies promote.