I have zero interest in Bitcoin, but the idea that terrorists finance happens through cryptocurrency is very naive. Terrorism is sponsored on the ground, with goods, not money that you have to convert to some other money first, and then buy things you need.
Money Laundering tends to be smallish sums deposited over time, resulting in large amounts. You can't wash 100MM in one go.
Terrosist Financing tends to be a very large number of small transactions from multiple global sources in a very short space of time into one account/wallet/location. Like crowd-sourcing, in fact exactly the same as crowd-sourcing.
Less risky than Bitcoin? In the end you have to get it out of the blockchain to be useful, so that's where the pointers from a law-enforcement perspecive are.