In the configuration manager for KLGA it gives you the option to use SODE jetways and I have that option checked. I assume the installer takes care of adding the sode jetways. I tried un-installing and re-installing the scenery but the jetways are still missing.
Not sure exactly how the failure of a 3rd party installer to install its own jetways has any relevance here.
Nothing in GSX could possibly affect 3rd party SODE jetways, not even an Exclude file could do that and, when you WANT to exclude 3rd party SODE jetways and replace them with GSX, you are first supposed to manually remove the SODE XML files in the SODE folder but, of course, if you did that by mistake ( is still not very clear from your message what you were trying to achieve ), the scenery installer should be able to restore them so, if it fails doing that, it has nothing to do with GSX.
Also, you must have some kind of mistake linking to the screenshot, since they are not visible ( probably they are not in a folder than can been seen in public )