1) I have built and installed SDL2 32 bit by adding "media-libs/libsdl2 abi_x86_32" to /etc/portage/package.use which apparently resolved Bug #25396 "Crash on startup - Linux port"
2) Using "--eon_force_display=0" to avoid the game or NVIDIA driver from using the second connected HDMI monitor/display, as reported within the game's logging.
3) I'm still getting a crash, with no obvious indicators per the game's logging. The game's log and Steam's Wine logging is attached, and likely a developer will be able to discern milder errors within the log for which are critical.