if the match was by payroll, I'd say it makes sense to include/exclude based on participants election. otherwise, unless there was something specific in the document, I would include it.
most of the documents I work with indicate a participant can make an election change anytime.
so I would view that as saying each payroll period I elect to defer, defer, defer..oh the bonus check I elect not to defer, and the I start up again.
otherwise, how do you handle something like only HCEs defer off the bonus and none of the NHCEs defer. I'd think if you don't include it then at the minimum you have to run a comp test because now you are treating it as 'excludable comp'...but I could be way off on my thinking there.