I want to pitch ManicTime to my company but we use Choco to install and update all our software. Currently some 3rd parties have added ManicTime install/uninstall scripts to chocolatey.org but they have to be updated every update and they are all out of date.

The it's just a simple PS install script that doesn't really change (unless you change your install requirements) the only part that needs maintaining by you (once created) would be updating the install HASH each update. That could easily be automated into your release pipeline!