There is structural strength contributed by the leading edge spar. It's been 15+ years since I built my Chipmunk (It had just been released by Goldberg at the time) and I can't recall how the LE was done on this kit. Would it be possible to splice a piece of LE wood to the foam you've installed?

Seeing how you have asked this question here in beginners, everyone will assume you have no or little building skills, whether this is true or not. Maybe what you've done will suffice, only you and your local experieneced flying buddies can really make a decision about the structural integrity of this repair!