Had this error during the Fatal Car Crash. No idea what it means, other than it appears broken. I see that you are unable to do anything about it, however I figured that I'd let you know anyway in the event that you get your issue taken care of. Also, for recovery software, I have a program called DMDE that I've used myself and it works great (I have fully recovered 4 hard drives that failed with it), just a suggestion.
Accident.cs:line 654
[9/2/2018 6:51:58 PM.159] at Rage.GameFiber.Main()
[9/2/2018 6:51:58 PM.159] LSPD First Response: ==============================
[9/2/2018 6:51:58 PM.159] LSPD First Response:
[9/2/2018 6:51:58 PM.163] LSPD First Response:
[9/2/2018 6:51:58 PM.165] LSPD First Response: ==============================
[9/2/2018 6:51:58 PM.166] LSPD First Response: UNHANDLED EXCEPTION DURING GAME FIBER TICK
[9/2/2018 6:51:58 PM.166] LSPD First Response: ------------------------------
[9/2/2018 6:51:58 PM.167] LSPD First Response: Origin: Game fiber "<UNNAMED THREAD>".
[9/2/2018 6:51:58 PM.167] LSPD First Response: ------------------------------
[9/2/2018 6:51:58 PM.168] LSPD First Response: Exception type: Rage.Exceptions.InvalidHandleableException
[9/2/2018 6:51:58 PM.168] LSPD First Response: Exception message: Operation is not valid because the specified Rage.TaskInvoker is invalid.
[9/2/2018 6:51:58 PM.168] LSPD First Response: ------------------------------
[9/2/2018 6:51:58 PM.168] LSPD First Response: Inner exceptions:
[9/2/2018 6:51:58 PM.169] LSPD First Response: ------------------------------
[9/2/2018 6:51:58 PM.169] LSPD First Response: Stack trace:
[9/2/2018 6:51:58 PM.170] LSPD First Response: at Rage.TaskInvoker.Clear()
[9/2/2018 6:51:58 PM.171] at RoadIncident_Callouts.Callouts.FatalCarAccident.<Process>b__132_3() in E:\GTA V mod development\RoadIncident Callouts\RoadIncident Callouts\Callouts\Fatal Car Accident.cs:line 654
[9/2/2018 6:51:58 PM.171] at Rage.GameFiber.Main()
[9/2/2018 6:51:58 PM.172] LSPD First Response: ==============================
[9/2/2018 6:51:58 PM.173] LSPD First Response: