no way to tell without you first telling us exactly what you have done, the steps you outlined are non-standard and it isn't clear from your posting if you even know how to do make the corresponding changes properly. Besides, it isn't even clear if you installed osgEarth first. So far, it looks like you are making this more difficult than it is. Just having osgEarth fgdata doesn't suffice, you need to install osgEarth first, then build SG/FG with osgEarth support.
You mentioned ldd, do you even see any osgEarth-related DSOs when running ldd against your binary ?
To me, it seems you missed quite a few steps here - why don't you simply go to the original thread, check out poweroftwo's instructions, my wiki article and proceed from there ?
If this is all about contributing osgEarth support to brisa's d&c script, that's obviously fine, but you should first of all understand what you're doing there
PS: Expect this thread to be split and merged with your other osgEarth thread.