Try Levelhike instead. I use one for Xbox it's great! And the amazon comments say they have excellent customer service. No i'm not endorsed by them
something like https://smile.amazon.com/Cable-Nintendo-GameCube-Super-Console/dp/B07Z5TDL2X/ref=sr_1_20?crid=2T7L57SMCH964&keywords=gamecube+HDMI&qid=1650315164&sprefix=gamecube+hdmi%2Caps%2C104&sr=8-20 works ok, not as good as the digital AV converter ones but better than composite and works with more GameCube models