here is what I would do.. I would get this .. cut off that power connector and replace it with this one. There is no need for polarity check because it is just on and off.
https://mnpctech.com/bulgin-modmytoys-computer-pc-power-reset-switch-mounting-plates-vandal-anti-res...Not sure how good you are with soldering iron but there are other ways too. you can electrical tape the connection or shrink seal them. This is just an example.. there are a few brands and placed offer a 2 pin connector with wire leads.
InWin 909 Silver RGB build
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