For the longest time, I've been working off an unstabilized version of the above gif. Now that Mr. Davidson has kindly stabilized it, so much helpful detail leaps out.
Look for instance at these two women [red arrows]:
Each is simply
waving with her hand------------------
This supplies a second reason----------along with the location of the hands (too far east of the man [light-blue arrow])*-----------to definitively rule out either of these women as the source of the fluttering object in Towner. The latter is certainly no hand.
If you doubt this double reason to rule out either of these women as the source of the waving object in Towner, just take look at these synced Bell & Towner frames. Make sure to check out the very different spatial relations between
a) the lady in back's waving hand and the head of the man in khaki (Bell)
b) the waving object and the same khaki man's head (Towner)
This has large implications. For it leaves us with absolutely no alternative to the conclusion that
the object we see being waved energetically in Towner is coming from the doorway.
There is literally nowhere else it could be coming from. (If you don't believe me, look at the full scene in Bell in the Quote section at the top of this post--------ain't no one there between street spectators and doorway.)
Once you have let this fact sink in, consider another.
There is only one person in the right position in that doorway to be waving this object: the man in the reddish shirt whom we've just seen in HughesAnd, to cap it all off, the presence of a figure at sitting height can be made out when the waving object is at higher elevation. We should just be seeing empty steps behind there, but no:
A man standing, waving the object: Mr. Oswald:
A man sitting, being blocked by the object being waved: Mr. Lovelady