Where does Jenkins run this from or run against? Bear in mind AutoIt needs to run "locally" on Windows machine you are testing. That means the Jenkins slave/agent that executes this must be a Windows machine running the test (locally). If it's ever remote, like Jenkins test executor is Linux, and you're targeting a remote Windows machine, you'll need to patch how you run AutoItLibrary:
* the simplest case is to use (Python) remote server to run/load AutoItLibrary on the Windows machine, you then load that remote server connection in your RF tests.
the other alternative is to use like PSExec.exe, SSH, etc. but that doesn't blend well with AutoItLibrary, that's more for connecting to AutoIt tool remotely with other frameworks rather than AutoItLibrary and RF.