Let's assume a paranoid Lich casts Wish, wishing that his most valuable magic artifact XYZ can never be removed from his side.
PC party member Gandalf later wishes for this item to appear next to him, without its owner.
What happens? And would the result be different if Gandalf had explicitly included a phrase like "override any contradicting Wishes", if that's valid to include?
Assume that the GM permits both Wishes; quote from the spell description:
You might be able to achieve something beyond the scope of the above examples. State your wish to the DM as precisely as possible. The DM has great latitude in ruling what occurs in such an instance; [...]