Issue has been fixed in InDesign’s latest update, Id 13.1.
Please update your InDesign for the resolution of the problem.
Ah, I see others are experiencing the same frustration. I have many scripts. I have them organized by number to keep them in a particular order. Since upgrading to macOS High Sierra 10.13, my scripts are completely out of order. As far as I can tell, there is no rhyme or reason for the order. Talk about frustration when trying to run scripts in a certain order. And the problem has been going on for several weeks. Why no solution yet?! I've tried several potential ideas to alter the order, but nothing has been successful. Seems we may be out of luck until a fix is brought to bear.