It was pretty depressing, the branch manager ended up writing her own caption a week later after no one else stepped up. My coworker was going to write down, "Derp!" but she never did. My idea was to go down the LolCats route (if all else fails, resort to cat humor) and write down, "Wutz Cheez?"
In fact, if this stupid picture is still up tomorrow, I am definitely writing down my caption and I am going to make my coworker write down hers as well.