I am telling you I have just tried the same scenario with SLI disabled and RTT enabled and its works just fine no flicker and it actually loads the textures for Logo's and KJFK has no error when loaded.
Of course it works fine. Since the problem IS caused by SLI, if you disable SLI, everything will work and, the "Disable RTT" option should stay on, which is the normal situation.
Maybe it's not clear enough: the reason why there's a "Disable RTT" option is that, on SOME systems (not related to SLI), SOME users reported an API.DLL crash in the Event Viewer AFTER closing the sim. This was totally harmless but, since some users were worried about it, we added this option so they won't see the error in the Event View anymore, at the cost of losing the Jetway Number.
That didn't had anything to do with SLI, at least initially. If you look other posts of mine, I think to have explicitly said a possible solution for SLI is changing the rttsli parameter in the Couatladdons.ini file, which can be tried, but not Disable RTT, which should always stay on.
My comment about a possible update, was just in case the problem wasn't fixed, not even with SLI disabled!
So for now my only work around is SLI off and RTT ON.
That's what I always said right from the start: JUST disable SLI, which is what causes the flickering, and use the program in what is the default configuration, which is "Disable RTT" NOT set.