If it were mine, I'd take out the existing quilting, then soak (not wash, just soak, with no agitation) the top and backing to clean them. Soak in Orvis, spin out, soak in clear water, spin out, soak again in clear water, spin out. Air dry. Then I'd quilt it myself, possibly with a new batting, if that batting has odors. Since it's so large, it will be hard to pin baste well and not get puckers, so I think I'd have someone with a longarm thread baste it before quilting it myself, or else quilt it using a three rail frame to quilt it, so there will be no puckers anywhere.