Unable to use Siri on managed iPads?

I have two iPads that don't seem to have the option to enable Siri. Nothing in the settings, and holding the home button doesn't do anything. I can mess around with the voice accessibility options, but Siri is just missing. Our configuration profile has Enabled Siri checked, and I just tried it one some new iPads and it works fine. I am at a loss and don't want to factory reset it if I don't have to.