How to test an issue in another user account on your Mac If your Apple wireless mouse, keyboard, or trackpad isn't working with your Mac as expected Check out these additional resources for further troubleshooting and to test the issue in a new user as this may resolve your issue: It sounds as if you've done majority of the necessary troubleshooting steps. I am more than happy to guide you in the right direction.
I understand that you are having issues with your Logitech G602 mouse and external Apple Keyboard intermittently disconnecting during normal use.
Thank you so much for using Apple Support Communities!