So very strangely, I've found that three map mods in dlclist.xml were causing LSPDFR to crash when trying to load into singleplayer. The exception is below:
[7/8/2024 2:32:59 PM.278] LSPD First Response: [TRACE] Started loading LSPDFR
[7/8/2024 2:32:59 PM.278] LSPD First Response: [INFO] Running LSPD First Response 0.4.9 (0.4.8943.27879)
[7/8/2024 2:32:59 PM.278] LSPD First Response: [INFO] Compiled on 26 Jun 2024 19:29:18 UTC
[7/8/2024 2:32:59 PM.278] LSPD First Response: [INFO] Copyright © 2015-2020, G17 Media, www.lspdfr.com
[7/8/2024 2:33:01 PM.730] LSPD First Response:
[7/8/2024 2:33:01 PM.730] LSPD First Response: ==============================
[7/8/2024 2:33:01 PM.730] LSPD First Response: UNHANDLED EXCEPTION DURING GAME FIBER TICK
[7/8/2024 2:33:01 PM.730] LSPD First Response: ------------------------------
[7/8/2024 2:33:01 PM.730] LSPD First Response: Origin: Game fiber "Plugin "LSPD First Response" main fiber".
[7/8/2024 2:33:01 PM.730] LSPD First Response: ------------------------------
[7/8/2024 2:33:01 PM.730] LSPD First Response: Exception type: System.AccessViolationException
[7/8/2024 2:33:01 PM.730] LSPD First Response: Exception message: Attempted to read or write protected memory. This is often an indication that other memory is corrupt.
[7/8/2024 2:33:01 PM.730] LSPD First Response: ------------------------------
[7/8/2024 2:33:01 PM.730] LSPD First Response: Inner exceptions:
[7/8/2024 2:33:01 PM.730] LSPD First Response: ------------------------------
[7/8/2024 2:33:01 PM.730] LSPD First Response: Stack trace:
[7/8/2024 2:33:01 PM.730] LSPD First Response: at Rage.Native.NativeFunction.CallByAddress(IntPtr address, Type returnType, NativeArgument[] arguments)
[7/8/2024 2:33:01 PM.730] at Rage.Native.NativeFunction.CallByHash(UInt64 nativeHash, Type returnType, NativeArgument[] arguments)
[7/8/2024 2:33:01 PM.730] at Rage.Native.NativeFunction.CallByHash[ReturnType](UInt64 nativeHash, NativeArgument[] arguments)
[7/8/2024 2:33:01 PM.730] at WmNPETcPKRMNlmjqVPKgDsXaHBRM.YgEZVRHfggoQicICJUFYHAAjNVjK() in D:\GTA V\LSPD First Response\LSPD First Response\Mod\LSPDFR.cs:line 464
[7/8/2024 2:33:01 PM.730] at WmNPETcPKRMNlmjqVPKgDsXaHBRM.mciTtfMWbMVbgYEmfidSWMdEvTHI() in D:\GTA V\LSPD First Response\LSPD First Response\Mod\LSPDFR.cs:line 161
[7/8/2024 2:33:01 PM.730] at Rage.GameFiber.Main()
[7/8/2024 2:33:01 PM.730] LSPD First Response: ==============================
[7/8/2024 2:33:01 PM.730] LSPD First Response:
[7/8/2024 2:33:01 PM.732] LSPD First Response: [TRACE] Thread CopManager #1 initialized
[7/8/2024 2:33:01 PM.735] LSPD First Response: [FATAL] Forced termination
[7/8/2024 2:33:01 PM.738] LSPD First Response: [TRACE] Released 0 entities from DefaultContentManager
[7/8/2024 2:33:01 PM.755] LSPD First Response: [INFO] LSPDFR has shut down
After a LOT of troubleshooting, I determined it to be an issue with map mods located in my dlclist.xml within update.rpf:
<Item>dlcpacks:/custom_maps/</Item>
<Item>dlcpacks:/forest_n/</Item>
<Item>dlcpacks:/forest_s/</Item>
<Item>dlcpacks:/vremastered/</Item>
Forests of San Andreas: Revised [Add-On | YMAP | YMT | CARGEN | LODs | OIV | SP | FiveM] - GTA5-Mods.com
New Realistic Forests of Blaine County + Abandoned Cabins [YMAP] - GTA5-Mods.com
GTA V Remastered: Enhanced [Add-On | YMAP | LODs | OIV | SP | FiveM] - GTA5-Mods.com
For the time being I've removed these from my dlclist.xml file but is there any other solution by chance?