NavMeshObstacle::RegisterObstacle() Crashing dedicated server [Update]

[RNG]

Hello. I've been using DynamicNavMeshObstacle guide for a while now. It works absolutely fine in listen server, however it crashes really quickly on a dedicated server. I've tried using the exact code from gems and starter kits, tried using just the barebones of it, but no matter what I do, NavMeshObstacle::RegisterObstacle() always, eventually crashes the server.

Here's the crash log:

[0034.19] Critical: Windows GetLastError: The operation completed successfully. (0)
[0046.79] Log: === Critical error: ===
Assertion failed: i>=0 && (i<ArrayNum||(i==0 && ArrayNum==0)) [File:d:\depot\unrealengine3-udk\development\src\core\inc\Array.h] [Line: 575]

Stack: Address = 0x40024419 (filename not found) [in E:\UDK\EBAET\Binaries\Win64\UDK.exe]
Address = 0x405b5fe5 (filename not found) [in E:\UDK\EBAET\Binaries\Win64\UDK.exe]
Address = 0x405b6ebd (filename not found) [in E:\UDK\EBAET\Binaries\Win64\UDK.exe]
Address = 0x4059f1f7 (filename not found) [in E:\UDK\EBAET\Binaries\Win64\UDK.exe]
Address = 0x405b7866 (filename not found) [in E:\UDK\EBAET\Binaries\Win64\UDK.exe]
Address = 0x405e6737 (filename not found) [in E:\UDK\EBAET\Binaries\Win64\UDK.exe]
Address = 0x405ec47d (filename not found) [in E:\UDK\EBAET\Binaries\Win64\UDK.exe]
Address = 0x405f0261 (filename not found) [in E:\UDK\EBAET\Binaries\Win64\UDK.exe]
Address = 0x3ffeefa7 (filename not found) [in E:\UDK\EBAET\Binaries\Win64\UDK.exe]
Address = 0x3ffec650 (filename not found) [in E:\UDK\EBAET\Binaries\Win64\UDK.exe]
Address = 0x3ffef30e (filename not found) [in E:\UDK\EBAET\Binaries\Win64\UDK.exe]
Address = 0x3ffec650 (filename not found) [in E:\UDK\EBAET\Binaries\Win64\UDK.exe]
Address = 0x3ffef30e (filename not found) [in E:\UDK\EBAET\Binaries\Win64\UDK.exe]
Address = 0x3ffe7679 (filename not found) [in E:\UDK\EBAET\Binaries\Win64\UDK.exe]
Address = 0x3ffec650 (filename not found) [in E:\UDK\EBAET\Binaries\Win64\UDK.exe]
Address = 0x3ffef30e (filename not found) [in E:\UDK\EBAET\Binaries\Win64\UDK.exe]
Address = 0x3ffe7679 (filename not found) [in E:\UDK\EBAET\Binaries\Win64\UDK.exe]
Address = 0x3ffec650 (filename not found) [in E:\UDK\EBAET\Binaries\Win64\UDK.exe]
Address = 0x3ffef30e (filename not found) [in E:\UDK\EBAET\Binaries\Win64\UDK.exe]
Address = 0x3ffe7679 (filename not found) [in E:\UDK\EBAET\Binaries\Win64\UDK.exe]
Address = 0x3ffec650 (filename not found) [in E:\UDK\EBAET\Binaries\Win64\UDK.exe]
Address = 0x3ffef30e (filename not found) [in E:\UDK\EBAET\Binaries\Win64\UDK.exe]
Address = 0x3ffec650 (filename not found) [in E:\UDK\EBAET\Binaries\Win64\UDK.exe]
Address = 0x3fff6ae7 (filename not found) [in E:\UDK\EBAET\Binaries\Win64\UDK.exe]
Address = 0x402cf9e9 (filename not found) [in E:\UDK\EBAET\Binaries\Win64\UDK.exe]
Address = 0x40afb1c8 (filename not found) [in E:\UDK\EBAET\Binaries\Win64\UDK.exe]
Address = 0x40adacae (filename not found) [in E:\UDK\EBAET\Binaries\Win64\UDK.exe]
Address = 0x40aed2ae (filename not found) [in E:\UDK\EBAET\Binaries\Win64\UDK.exe]
Address = 0x40aef512 (filename not found) [in E:\UDK\EBAET\Binaries\Win64\UDK.exe]
Address = 0x40af26bf (filename not found) [in E:\UDK\EBAET\Binaries\Win64\UDK.exe]
Address = 0x40b951d1 (filename not found) [in E:\UDK\EBAET\Binaries\Win64\UDK.exe]
Address = 0x4052bef0 (filename not found) [in E:\UDK\EBAET\Binaries\Win64\UDK.exe]
Address = 0x40475b23 (filename not found) [in E:\UDK\EBAET\Binaries\Win64\UDK.exe]
Address = 0x4042fd8d (filename not found) [in E:\UDK\EBAET\Binaries\Win64\UDK.exe]
Address = 0x4155cc16 (filename not found) [in E:\UDK\EBAET\Binaries\Win64\UDK.exe]
Address = 0x4155daf7 (filename not found) [in E:\UDK\EBAET\Binaries\Win64\UDK.exe]
Address = 0x4155dc4a (filename not found) [in E:\UDK\EBAET\Binaries\Win64\UDK.exe]
Address = 0x94e816d4 (filename not found) 
Address = 0x94e31ee8 (filename not found) 
Address = 0xf44724ca (filename not found) [in C:\Windows\Microsoft.NET\Framework64\v4.0.30319\clr.dll]
Address = 0x94e8124e (filename not found) 
Address = 0x782d96   (filename not found) 
Address = 0x3fde0000 (filename not found) [in E:\UDK\EBAET\Binaries\Win64\UDK.exe]
Address = 0x3fde0000 (filename not found) [in E:\UDK\EBAET\Binaries\Win64\UDK.exe]

[RNG]

Apparently, this is caused by having a custom Scout class. Even if it is empty, it causes a crash. I'm using an empty project and switching back to UDKScout fixed crashing.

NavMeshObstacle::RegisterObstacle() + Custom Scout class (even if it is empty) doesn't work.

Edit: Pylon settings doesn't matter, it crashes anyway, custom scout class is still looking like the culprit.