Correct handling / negotiation of non-cash EBITDA

I am under LOI for an attractive, diversified company with nice growth, several lines of business, and a nice asset base.

However, in diligence, we learned that a chunk of their 'revenue' is actually a non-cash inventory transformation. I've learned that in certain sectors, it is not uncommon accounting practice to put inventory value transformations onto the P&L, typically in COGS or revenue. That said, we now have a disconnect on what EBITDA is, as I did not have the foresight to exclude this sort of thing from my EBITDA calculation, and even if it is EBITDA to the company, I can't use it for running the business.

The seller and I have a good relationship, and I do not suspect maliciousness -- but the difference in EBITDA would amount to a gap of several $MM in enterprise value. He doesnt want to retrade, obviously.

Has anyone seen such a situation? Interested in any clever deal structures that might work around this.