In common usage, we don't always use words in their technically correct sense. Even scientists, engineers, and technologists are often loose with their use of language amongst themselves, which can often cause misunderstandings to those lay persons who stumble into the conversation. Also, there are debates even in the scientific community as they come to understand what certain words ought to mean. For example, I think it's pretty clearly understood NOW that 'random' and 'chaotic' are not synonymous - even among the educated laity.

It's not clear to me in the example you give that the usage was incorrect, although I suspect by 'random" in this instance, the person meant "unexpected."