AdamG,

Given the character of Afghan society that is byzantine in its intrigues and relationships an accusation of ISIS activity can hardly come as a surprise. Cast your memory back to the period between the post-Soviet exit to the victory of the Taliban (backed by Pakistan) Afghanistan was wracked by a bloody civil war.

Whether a ANP chief in Helmand Province is the most reliable source is a moot point. If you were engaged in an insurgency and under pressure from the Taliban, what better way to try and entice old allies to give you support?