Ok, this should be fine. Note that because it has the edits applied to it, if you load this file the pre-installation test will still show it as failed (because it is already done so the mod can't do it, if that makes sense).
So, go to the package manager and install the mod regardless. As soon as it is done use your ftp to load this edited copy of Sources/Load.php into place. The result should be a working mod.