It seems all of that code could be avoided if you had a proper deployment system.

I foolishly commented out its cronjob while working on its script, and left it commented out, so I missed some data points.

That's the problem: You edit stuff on a production machine.

Here's my understanding on how things should go:

• You have a source repository for the script
• You have a test suite for the script
• When you need to do a change, you do it on your local developement machine, and run the test suite
• When you're convinced that your changes are good, you check them in
• You check out the new version on the production system. The process of checking out should be only a few seconds, no need to disable any cron job
• For additional safety, you can install hooks in your version control system that prevent check-ins that make the test suite fail

Maybe I misunderstood what you're doing, but it seems you're only adding layers of sanity checks for non-existing deployment solutions. See also: Technical debt.