The Appraisal Files

Had a new one today, completed an assignment that the appraisal did not support the sales price. I used only homes on the same street, sold in the last year and built by same builder, however I was contacted by the LO with information supplied to him by the seller, that  two of the sales used were sales that something of value had been traded in on the home and the actually sales price was much higher than what was listed in the MLS. I always verify a comp sale by public record, the tax assessors records has the sale amount of both sales the same as the MLS. My question back to the LO was " Had the two sales been underreport to the tax office to avoid property tax? This is felony in Kentucky with a $10,000 dollar fine as penalty. I am very interested what the reply will be.