That is an organic fertilizer and if the nurseryman says its safe for your Bermuda I think you should trust the man who knows.
Many fertilizers are explicitly suggested for some types of grass and some should not be as also is some types of broadleafed weed killers. Normally these are safe to use on natural grass but for some southern grasses broadleafed weed killer is that, a killer. The importance of reading the label and asking question is truer than ever.