Targeting MovieClips as vars from main frame

Ok, I have the MovieClip named dessin, which loads another MovieClip named dessin (dessin.dessin). Now, there is a MovieClip named displayPlane, in the new MovieClip (dessin.dessin), in the MovieClip named displayPlane, there is a variable, which goes as follows:

Actionscript Code:

var _loc3 = displayPlane.attachMovie("displayNode", "displayNode_" + projectCount, projectCount);

inside that clip, there are multiple MovieClips in vars, I am trying to specifically target one var, the following:

Actionscript Code:

var _loc8 = this.attachMovie("closeBtn", "closeBtn", 5);

I have tried this code to target that specific MovieClip with no success. Please HELP.

Actionscript Code:

_root.dessin.dessin._loc3._loc8

What am I doing wrong????

Provide FLA please :)

Here is the fla (sample) of what will be in the MovieClip in the main frame (dessin.dessin).
Pay no attention to the fact that the closeBtn is not working correctly. It will work correctly on the REAL file.