you are confused and I am not your "buddy"...
Read more about HTLC
https://bitcoinops.org/en/topics/htlc/


What you refer to "private key" is EXACTLY the way you move sats in a LN contract (HTLC).

Buddy, you are lost. Why do you hold a private key if not to prevent the money from moving?

b4bd9e8416

Sats in a LN channel are MOVED anytime you want.

What specify that multisig contract is about how much owe to each others.

If a LN contract will really lock sats, then is against its purpose...

lightning

Does lightning have incentives for centralization?

BallLightning

[Locked - means you cannot move it.](https://dictionary.cambridge.org/dictionary/english/locked)
Sats in a LN channel are MOVED anytime you want.
What specify that multisig contract is about how much owe to each others.
If a LN contract will really lock sats, then is against its purpose...