You must be near a sanctuary to get to a grove. Type in /grove and select your grove name. Do the same again to exit and select EXIT GROVE.
You must be in your own grove first. Then type either /warpi [grove name] or /warp [player name].
If possible, stand near the invisible prop and use the /sceneryBrowser to find objects that are near to you (you can use “Radius” to restrict the distance). Click on the object in the browser and press the delete key.