As it was also "part of your job" in the dream to deliver the snake - I'd say the snake symbolizes something, which you may or may not be fully aware of at work which presents a hidden danger to you. Or, it could symbolize someone at work who is not to be trusted, ruthless, and cold blooded, so to speak.

In any case, I think that your dream is just warning you of potential risks, dangers, or fears at work, some of which you already know about and some which may try to bite you in the arse despite your best intentions. Your decision at the end, indicates that you might be willing to deal with the potential consequences, whatever they may be.

That is my sidewalk psychiatrist interpretation of it, anyhow..