Dad for a Minute

None of these options are actually how you are supposed to hook up a washer drain but to do it right would involve hiring a plumber, opening walls, and routing the drain lines correctly. Good luck with your project, and remember, Youtube is your friend. A basic understanding of PVC pipe, how compression fittings work, how flexible rubber fittings work, and how washer drains are typically installed will go a long way towards helping you fix your particular issue.

Oh, and If the right side isn't capped in some way then I would do so, any backup in the drain below that connection will push the water out that opening, but that's a whole separate problem (take off barbed fitting, add PVC pipe and cap).