I did what you said not to and googled, but a cursory perusal suggests that Table 5-3a & 5-3b have some values for American Chestnut:
https://www.fpl.fs.usda.gov/documnts/fplgtr/fpl_gtr190.pdf
https://www.newcivilengineer.com/latest/wsp-faces-fiu-bridge-collapse-lawsuit-despite-not-being-involved-in-project-28-09-2020/
I'm fairly certain this has been discussed in the FIU pedestrian bridge collapse thread if not elsewhere. The gist of it is that since WSP purchased the Louis Berger...
Part of me didn't want to post anything at all, since fatal injuries are not opportunities for levity. But another part of me fixates on technical accuracy (to a fault, some would say). That part of me needs to inform the would-be Darwin Award nominators that since Mr. Hughes is survived by 2...
Without any other information, I'd guess he's looking for coverage for services you'd rendered in the past. Have you rendered any services to this client in the past?
This article doesn't address mid-span support for Dox Plank specifically, but does state that "...shoring in the center of the span was sometimes employed to increase the clear-span capability of the members..."...