I wonder… regarding this tx where cost was 66700USD…

It’s actually easy to find out. From each transaction you can click the block height:

And from there you can see who mined it:

It went to miningpoolhub_1.

It would be very difficult to catch a specific mining reward… you would have to convince all the other miners to stop mining to ensure your chance of getting it, or control at least 51% of the mining nodes.