To directly answer your question, a secondary closed approach can be used after an initial open approach. However, my suggestion to you is to revisit open rhinoplasty.
First, it sounds to me like your collapse is the internal valve, not the external valve. If it is the nasal sidewalls, roughly the middle third of the nose that bellows, that is the internal valve. If it is the nostrils that collapse, then think external. The fact that you mentioned nostril flare to me suggests internal.
If that is the case, a spreader graft is often suggested. Yes, they can be placed through a closed rhinoplasty. However my experience has led me to realize that there is more precision in their placement when and external approach is utilized. Plus, an additional "flaring stitch" as described by Stephan Park (you may want to look that up on scholar.google.com) is also added to ensure an improved airway. That requires an open approach.
You have come this far with your decisions, including the original open procedure. Don't let the revision approach drive your decision. Decide on the surgeon and his or her proposed solution as your next step.