In iOS 12.2 Apple disabled the gyro/motion sensor in Safari, it could be turned back on in Settings > Safari > Privacy >Motion and Orentation Access
but in iOS 13 ......
That setting has now gone, there is no way to turn the gyro on for Safari, if you have Chrome or Firefox browsers the gyro works without any intervention by the user.
I'm assuming that within the iOS 13 developer API there is a way to prompt a user to enable the gyro on a site by site basis, if this is the case then it would need to be implemented by the Enscape devs for the panorama viewer.
I know that iOS/TabletOS 13 is still in beta but we're so close to public release that I don't see the setting coming back.