No coins are forever lost.

You have to learn a bit more about bitcoin. There are quite a number of scenarios in which the coins are really lost forever.

It's already somewhat late. I've checked one of the addresses and the coins were mined in November. Many others were already mining Bitcoin then.

adress use mixer! - split into smaller amounts and into many addresses

I'm not surprised. The owner probably wants to avoid unnecessary attention from.. various people.

The private keys, will be found by someone else and the coins will be moved.

I'll only add this: