Hi there!
Great choice for your related text! I think there are some connections you could make to discovery - perhaps the discovery aspect of your essay could relate to renewed perceptions. Miranda in Tempest has renewed perceptions about her family history in Act 1, which lead her to discover that her world was not as she thought (there is a disconnect between reality and perception). Similarly in Tell Tale Heart, you could draw the same connection by saying how the narrator thinks the old man is dead, but this is of course, made very ambiguous (there is a disconnect between reality and perception). I suppose you could also connect the two through the themes of murder, and how the plotting of a murder can lead to discoveries about oneself and their mental psyche. Anything that connects to renewed perceptions would work in your favour, rather than making actual discoveries.
Good luck!