https://bugs.winehq.org/show_bug.cgi?id=48482
--- Comment #13 from Stefan Dösinger stefan@codeweavers.com --- WINEDEBUG=warn+heap doesn't write anything unless it detects corruption. It enables some extra code that will fill freed Heap memory with 0xfeeefeee and newly allocated ones with 0xfeedfeed (or similar. not sure). It also verifies some extra canary values when operating on heap allocations.
That making it large address aware doesn't help suggests that the heap use is not the issue here. Is the virtual memory size still in the 3+ GB range at the time of the crash? Heap corruption is pretty unlikely too. warn+heap is not guaranteed to catch it, but very likely.
So next guess would be a race condition. Did you try to force it to one CPU core with taskset? (e.g. taskset -c 1 wine kotor.exe)