Walks with gun: First, IF lined bags ever existed they were extremely rare. I never found any. I then spent some time talking with some of the more famous bag makers as I figured they probably (hopefully) had researched their craft. They sort of pointed out the obvious: very few original bags of any sort remain and most are held in museums, etc where all you have to work with is a photo- can't tell if there was a lining. If you can find a nice curator they may look inside the bag but if it is in a sealed display case- you are out of luck. In any event several told me they had seen original bags with a lining (how they knew the bag was original I don't know) and as I said, they claimed the lining was held in place with the stitches. On these stitches, if it was a plain bag there was the stitching around the perimeter. On the back panel there were stitches for the carrying strap ends. On the front panel, there was often a decorative stitching of a star, moon, or animal.
But- all in all, you are dealing with a rare item if in fact any originals actually existed. I am sort of putting my faith in the fact these craftsmen told me the truth- so second hand info.