It's super old and it is hollow
I was told it might be worth some money
Who told you this?
And why are you not believing them (if you were, you'd be going about the business of selling your dead trees for profit, not asking for confirmation on a message board. ) Am I wrong?
So why do you not trust this person who told you these trees might be worth something?
I think that is the big question, here. Surely you have qualified or interested people to ask, right in your region?
Around here, even choice old-growth hardwoods go for under $200 a full cord, delivered. Cherry, walnut, oak etc. Dime a dozen on craigslist in winter, for burning in fireplaces.