According to the Kansas Kids Wrestling Rules attached below it would appear he should have proof of enrollment in a Kansas school which would provide verification of his Kansas residency:

For the purpose of eligibility of entering a Sub-District or District tournament, a competitive member must be a resident of Kansas and/or be enrolled in a Kansas educational school system. Special cases to this rule are subject to notification and permission from the Executive Council. The State Tournament Director will be notified of any person permitted to wrestle under this provision.

I would expect that due to the suspicions it shouldn't be a problem providing this information.