There is one and only one question in this case. Why would any pilot request clearance to below the known peak altitudes of stratocone volcanoes in conditions in which those peaks cannot be seen?
According to Mulya Abdi, General Manager of Soekarno-Hatta airport which quoted by several Indonesia online news and newspapers, the pilot request received by ATC when they flew above Atang Sanjaya airfield (elevation:171 m) west of small town Bogor (elevation:256 m) which approximately 8 NM east of mount Salak. I read those articles in Indonesia language and will disregard these soon as any news development coming since I read many conflicting reports about these circumstances.