@nprofile1q... also thanks for the pictures.
The barely-pictured shower curtain in your first picture gave me an idea.
My electric service panel is VERY close to my plumbing, and it has always made me extremely nervous that a leak could spray the panel.
I'll be doing that this weekend, and I owe the idea to the leak in your parents basement and your post, so thanks!
I don't know why I never considered just putting up a plastic sheet/shower curtain before now.