The Harris QD bipod I have will not work with the setup you show. It needs quite a large surface to mount against (see Harris bipod flange below); at least 3/4"-1" on both sides for proper bearing/support with 1.5" or better clearance either side of the QD swivel at or below the surface of the bipod attachment flange. The QD attachments linked below look like they will work for you: lots of excellent choices nowadays. Mine mounts on the E2 front rail via the QD stud as seen below. Just use a QD sling swivel on the front of the sling: it can be attached to the QD attachment on the Harris bipod or to the QD on front of the rifle with the bipod not installed. HTH
It looks like there will be a problem with the sling swivel if the bipod is mounted ahead of the button. I'd suggest using the button for your bipod and installing a new swivel that fits the Picatinny rail.
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