Because Violation isn't the name of the eePanel. It's eePanel1 or eePanel3 or something like that.
You also haven't specified what your strata problem is. I'm too busy/sick/lazy to go check in-game, but anchors shouldn't change the strata. It's possible, but strata is something that's supposed to be inherited from the parent as far as I can tell (and as far as wowwiki says).
I get the same error if i use eePanel1 as name. If i use a name that doesn't exist (not eePanelx or a name i gave to a panel) i get an error about the name and not about GetStrata.
What happens with the strata is that as soon as i enter the script in the add script window, the panel goes to it's place but is between Violation. The panel hides the bars and the header of Violation, but the text on the bars is visable. When i switch the strata to low and back to background the panel is in the background behind Violation. The effect is the same when i only use the parent part of the script and remove the anchor line. So my conclusion is that the parent part of the script modifies the strata somehow.