Better safe than sorry (guilty pleasure)
"On the ground, NASA continues to examine images of Atlantis's thermal protection tiles. Although mission managers have declared them "safe for re-entry", the shuttle's crew was earlier today told that "imagery from scans of the underbelly and scans of the crew cabin did not sufficiently overlap"."
Bugger it, I say send Endeavour up, see which one's most fit for purpose and leave the other one up there - or de-orbit it on autopilot (which they can do). Nothing to lose anymore, it's Atlantis' last mission! I wanna see two shuttles tethered!!!