Is there any other way to send transaction bundle to miners besides Flashbot?

https://ethereum.stackexchange.com/questions/145217/is-there-any-other-way-to-send-transaction-bundle-to-miners-besides-flashbot

I’m studying flash bot recently, and I found by chance that the first few transactions of this block(https://etherscan.io/txs?block=16655452&ps=100&p=2) seemed to be a flash bot bundle (because the gas price of the last transaction was much higher than the average value, indicating that the bundle sender gave the miners a very high reward to enable the bundle to be executed).
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However, I didn’t find any information about this bundle on https://flashbots-explorer.marto.lol/ (flashbot explorer), because the result returned by the webpage shows that there is no flash bot bundle on this block.
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How to judge whether this is a flash bot bundle? If not, could it be something similar to the flashbot bundle? How does its sender build and send it?