As fas as I know, a foreigner can hold a company in the US and conduct business for US clients while physically being offshore.
There may be some process or forms to file as your status as a company owner will change from resident alien to non-resident/ foriegn entity.
Your friend need to consult a tax lawyer that can guide you on the compliance requirements.
No issues, if this is done following all legal obligations towards US government and there is no breach of compliance.
Note that they should also consult a CA in India that can guide and make sure the India tax compliance is also met.