As you suggest, the Rees list is a very partial 'Officers, Gentlemen and Ladies' list from sources immediately available after the lifting of the Siege. Conspicuously missing are the majority of 'lower order' ODs, 'men', women (as opposed to ladies
) and children.
I've been working, for a number of years, on a 'definitive' list of 'Original Defenders' of the Lucknow Residency, from 30 June 1857, to the arrival of the Outram-Havelock 'Relief' force in September. See the forum on this topic on the Indian Mutiny thread. I believe that this is the most complete, though by no means definitive, and not published list yet compiled.
Of the approx. 3000 original ODs, I've identified, with great certainty, about 1550 of the 1700 ' European' ODs. The Indians are very difficult to identify, as most are identified only by their occupation in the various sources and a large number left the besieged Residency compound at various times during the Siege, ditto a significant number of the 'Native' troops who had remained loyal from the beginning of the Siege.
Having recently retired, I'm going to make one last effort to get a few more names before attempting publication. Any suggestions as to how the latter might best be done are hereby solicited.