Can the {R}{R} energy used for Volcanion's "High-Heat Blast" attack count as part of the "at least 4 {R} Energy in play" bonus damage?
Yes, it can.
Source: Unbroken Bonds FAQ (2019-04-19), TPCi Rules Team (2019-05-02)

Relevant cards

Note: All applicable cards may not be listed below.
SM10_25
SM10_25