This is kind of hard to answer based on the info you've given.
What are the credentials of the other provider? If it is another LCSW the answer is absolutely not. If it is an MD or a PhD or a PsyD, then you need to check the state laws and the guidelines of each insurance carrier. Also, even if the other provider is not in the room, is the LCSW going over the cases with the other provider after the services were rendered? The supervising provider doesn't necessarily have to be present during therapy, but there would be other guidelines, such as reviewing the care, etc. If the other provider is not truly supervising but just providing a means for billing to get paid, this is a big no-no.
If the LCSW is required to work so many supervised hours to get the license, and the other provider qualifies as a supervising provider then it may be fine.
Good luck!
Michele