Broken Down in N. California..north of Eureka

GF was driving our Class C, 1999, E350, V10, 22' and as we were headed downhill, she apparently pulled the shift lever down into first instead of second and the engine made a loud screaming bang. We coasted to the side and after numerous attempts at restarting, it would barely run rough and not at idle. Tow truck took us off the hill to a RV park. Any ideas as to the possibility of a toasted engine or would this be transmission? No leaks under RV.

Also does anyone know of a reputable repair shop in Eureka? We have Good Sam premium coverage