Feel free to use alternative words to clarify "endpoint" to particular users, but make sure your IT colleagues understand what an "endpoint" is.
In the IT security field, "endpoint" specifically means any computing device (and particularly an end-user device) that might be managed, patched, scanned, compromised, encrypted, etc. Your IT colleagues need to learn this usage and be familiar with it. You imply that they're only familiar with this usage in relation to endpoint encryption. That suggests they might benefit from some broader reading.
But, outside of IT, there's no obligation for other people to learn our jargon. So use whatever word is most easily understood. If you're just using McAfee Endpoint Threat Protection to prevent malware on Windows laptops, say "we install McAfee Endpoint Threat Protection on your laptop to protect it against malicious software." If you're covering desktop PCs and Macs, too, then its "...on your PC or Mac..."
Source: I work with similar software.