Offer to lease

Ive recently been approached to lease mineral rights in the Clark 43B. It is presently being operated by Diamondback but Endeavor had it for many years. The company wants a 3 year lease with no option to extend. My issue is ethically, it feels wrong to lease something that is already leased! Ive offered to do a top lease. I wish I had the original lease agreement(probably dates back to early 60’s).Im being told the well is about to be shutdown due to poor production. Any thoughts, suggestions or ideas would be appreciated.