Did the accident aircraft have brake mean effective power gauges? More than MAP + RPM, BMEP shows a direct torque (and hence h.p.) output. I have a very few long-ago hours on CV440, and am no expert on the R-2800, hence I probably would defer to the superior technical knowledge of the engineer when it came to nuances. Once you do that though it might be too easy to rely on that knowledge past the point of (operational, pilot sh*t) prudence.
I think the US Navy crashed a 440 in similar circumstances in the 70’s. Engines mounted in the wing present fire-related issues that we moderns have not had to consider for several generations of aircraft.