For the benefit of anybody else trying to delve into this period, and being repeatedly cast up on shore, I did find a book that fills in an important gap in what I think of as "the Matter of Fredericksburg." A German geneologist uncovered, translated, and published a bundle of letters from the Texas branch of her family. Die Kettner Briefe/The Kettner Letters (Ils Wurster; Chas. A. Kettner, Peter Benji, Carol Okesa & Jerry Okesa; 2008; Lulu.com but don't hold that against it) contains only three letters describing conditions during the war, plus one from 1860 and one from 1866. In addition to interesting news on lifestyles and details on what they could easily get themselves as opposed to what needed importing (the 1865 letters describe the desperate state the family is in for textiles - they've eaten so well they've gained weight, but Mrs. Kettner has one black silk, the rest of her clothes have been cut down for the kids, the men and boys have worn nothing but buckskin for years, and they want sheets, bandages, corsets, caps, cuffs, collars, and fabric of all kinds), Kettner tries to explain about martial law and the Haengerbande to his parents without wincing away into generalities the way the memoirists do. In particular, his account of the events of 1864 fleshes out many of the hints I've seen dropped elsewhere, so that I think I finally have a handle on what happened and to whom after Louis Schuetze was lynched.
If you've ever read Fredericksburg's 50th anniversary celebration book and wondered who the Llano Leatherjackets were, who attacked the jail why, and what the outcome was, this is the book for you. You still won't know the identities of the "persons still living" for whose sake this information was reduced to such a skeleton, but if you've been rooting around in the archives enough you might be able to make some shrewd guesses.
Still nothing of that sort for Medina and Bandera counties; but I aim to infiltrate the geneologist networks and vacuum up whatever crumbs I can.