Agree with Tartan that embroidery thread is too fine for quilting. 30-, 40-, or 50-weight 3-ply cotton thread is typically recommended for quilting as it offers the strength needed to hold the three layers together.
I would hesitate, however, about finishing the quilt with a thread that is already showing signs of stress--before the quilt has transitioned into normal, everyday use--as I fear you may be constantly repairing it, which may turn out to cost you more time in the long run than had you ripped out the quilting stitches you've put into it so far.
A year ago, I helped repair a botched binding job on a very large quilt. It took 2-1/2 hours, but I got real comfy, listened to one of my favorite movies, and it wasn't so bad.
Whatever you decide, I hope your hubby loves his new quilt!