I believe only Jane made this quilt for the following reasons
The signature block actually states how many pieces are in the quilt
The quilt is actually signed, (rare for the time which shows a great deal of pride was taken in the quilt)
There is documentation that Jane Stickle won a prize for quilting at the Bennington County Fair for best pieced quilt the same year this quilt was completed
The differing textiles have been attributed to a relative of Jane's was a tailor and had many scraps to give her (from the museum display placard)
Here is a fun article where I got many of these factoids.
http://www.benningtonbanner.com/news...bit-opens-next