That's a funny (bad faith) angle you took it. I thought were talking about personal cheat sheets for general programming and tools, not work and proprietary stuff.

The alternative and typical options that nobody bats an eye at for doing this kind of thing (3rd-party big tech cloud) are much worse from a data hygiene perspective. If you're going to be that distrustful of personal phone usage by employees, you're running a prison instead of a workplace and replacing all thought with pointless checklists. That slippery slope never ends.

From your perspective, the best security posture is for employees to return to the office without any personal belongings so we can be extra super secure? It's too bad we can't erase their memories while we're at it since being a programmer is knowledge work.

Don't tell any authority that you are doing a thing, unless you have a good reason to tell them. It cannot possibly help you, it can only result in them telling you you can't do the thing any more.

And don't talk to police as a suspect. (I'm not sure if the rule still applies if you are the one reporting a crime)