Software Engineer seems a pretty safe choice.
Also, if they are Canadian they might get their goose feathers extra ruffled. https://en.wikipedia.org/wiki/Software_engineer#Canada
https://en.wikipedia.org/wiki/Software_engineer#United_State...
edit I may have been mistaken and the word engineer itself may be non-protected, but the term software engineer specifically is protected in Florida:
http://www.leg.state.fl.us/Statutes/index.cfm?App_mode=Displ...
That said, in my experience all manner of technical professionals (and even not so professionals) in Texas do routinely call themselves engineers whether they're supposed to or not.