All perfect praise be to Allah, The Lord of the Worlds. I testify that there is none worthy of worship except Allah, and that Muhammad is His slave and Messenger.
We have no information about the man whom you mentioned in the question, so we recommend that you consult the scholars and Islamic organizations in the country (where he lives); it is most likely that they will have information about his condition, ideas and activities, and are, therefore, more able to issue an appropriate ruling on a man like him.
It should be mentioned that, in general, one should not hasten to declare someone as a non-Muslim. Rather, there are some Islamic conditions which the scholars have set, and which should be met before doing so.
If a person’s Islam is proven with certainty, then it cannot be overruled except with a similar certainty.
For more benefit, please refer to Fataawa 8106 and 87963.
Allah knows best.