This is what the FAM says.
Errors in Choice of Country of Chargeability: If the entrant chooses the wrong country of chargeability at the time of the initial entry, the error will generally be disqualifying. However, if a DV applicant chooses a country of chargeability on the DV entry form that is within the same geographic region (one of the six) as the correct country of chargeability, and you determine that the applicant gained no benefit from his or her error, and there are no fraud concerns, you may continue processing the application using the correct country of chargeability in IVO. Post may need to obtain additional DV number(s) for the correct country of chargeability from the Immigrant Visa Control and Reporting Division (CA/VO/DO/I), as necessary, via a VISAS FROG message (see 9 FAM 604.2-1).
https://fam.state.gov/fam/09FAM/09FAM050206.html
It instructs officers that they “may”, not that they “must”. If you are set on this and don’t mind risking the money, you could take a copy of the above and argue your case, but (and this is just my opinion) I don’t see that they are forced to do this. That said, I would think a reasonable officer would do it. I’m guessing your consulate doesn’t do an awful lot of DV interviews?
As an aside it’s interesting to see an embassy take the time to notify an applicant in advance that they expect to disqualify them and warn them of the consequences. Never heard of it before, normally people only find out when they arrive at the interview.