<sigh>
lol ok

You have no evidence your private key is the only key that can spend a utxo.

This property of bitcoin depends on the ECDSA encryption it uses being mathematically sound and the implementation being correctly coded

YOU *TRUST* THE BITCOIN COMMUNITY WHEN THEY TELL YOU THIS IS SO.

YOU ARE ALREADY RELYING ON CRYPTOGRAPHIC PRIMITIVES YOU DON'T UNDERSTAND.
YOU JUST REFUSE TO ACKNOWLEDGE IT.