My Late Father's Business Partner Is Claiming A Verbal Agreement Gives Him 50% Of The Property My Father Left Me In His Will. Is This Enforceable?

Location: North Carolina
My father passed away in January after a short illness. He left behind a clear, notarized will that was drafted in 2021 with an estate attorney. Among other things, the will transfers ownership of a commercial property to me, his only child. The property is a small warehouse unit my father owned outright, no mortgage, no liens, valued at roughly $340,000. Probate has been straightforward so far and the property was set to transfer to me within the next few weeks.

Last Thursday I received a certified letter from an attorney representing my father's former business partner, a man I'll call Gerald. Gerald and my father ran a small logistics operation together from 2014 until about 2020 when they formally dissolved the partnership by mutual agreement. I have the dissolution documents. Gerald's attorney is now claiming that at some point before the dissolution my father made a verbal agreement promising Gerald a 50% stake in the warehouse property in exchange for Gerald agreeing to walk away from the business without seeking compensation for his share of certain equipment. Gerald says there were two witnesses to this conversation. Neither witness is named in the letter. No written record of this agreement is referenced anywhere in the documment because, according to the letter, none exists. Gerald is asking me to either deed him half the property or compensate him for his alleged 50% interest before the probate transfer completes.

A few things I know for certain: the warehouse appears in my father's estate inventory as his sole property with no encumbrances noted. His estate attorney has no record of any agreement with Gerald. And my father, in the last weeks of his life when he was still completely lucid, never mentioned Gerald once during any of our conversations about the estate. My question is whether a claimed verbal agreement about real property transfer is even legally enforceable in North Carolina, and whether Gerald's attorney sending this letter during probate has any actual power to delay or complicate the transfer that is already in progress.