To get a list of WMO,CYC matching some QC position, you can do something like:
https://erddap.ifremer.fr/erddap/tabledap/ArgoFloats.htmlTable?platform_number,cycle_number,position_qc&platform_number=~%226903075|6903076%22&position_qc=~%221%22&distinct()&orderBy(%22platform_number,cycle_number%22)
This is an example where I select profiles from floats 6903075 and 6903076 having a QC position of 1
If you want to allow for more allowed QC, list them with a | in the request:
https://erddap.ifremer.fr/erddap/tabledap/ArgoFloats.htmlTable?platform_number,cycle_number,position_qc&platform_number=~%226903075|6903076%22&position_qc=~%220|1%22&distinct()&orderBy(%22platform_number,cycle_number%22)