The transaction made by the OP seemed legit to me even though he paid the seller using bitcoin. It is possible that the OP did not mention payment via bitcoin on the proof of payment [transaction receipt] because he knows that bitcoin is illegal as a means of payment in his country. This allows him and the seller to sign a receipt with the estimated value of the payment in fiat instead of bitcoin which is not legalized by his country's government.
He has option with payment proof use price bought plot of land measuring after converting with bitcoin values without have use 1 bitcoin as payment proof, I think if country still not allowed using bitcoin as legal currency transaction when get problem he has chance losing plot of land measuring bought. But if both of them are trusted is not worry what ever payment currency kinds use for transaction but at the future we don't know about seller looks trusted or not. But for keeping plot of land measuring better change name and he use his name take care about what happen at the future later.