Hi, this is not possible since CallCommand is the thing called when you click on an icon to do an operation so its wrap undo creation and so on, which are step not allowed in a thread and since the executing of tags are threaded, this is not possible. For more information about threading in Cinema 4D please read Threading Information.
And to be honest I don't really see any workaround for you, which doesn't require some plugins or some kind of complicated hack.
Since it's a follow up from Record Keyframe of Object's property when it changes (Python; is it possible?) I will wait until you answer to the previous one because maybe this will already fix your issue.