I think I found the problem.
Due to the new version of ArmA, one of my mods apparently has been partially overwritten or deleted. I just downloaded it via the Steam Workshop and the mission is playable again.

@Koala
I can't actually play my mission without the mods, so sadly that is no option.

@Koala
Thanks for your response!
I deactivated all mods and verified the game's data files, but that didn't solve the issue either.

@Adam
Thank you very much for your response!
I checked the page file and its size is 7168 MB.
I also checked if any of my hardware components is overclocked and got to the result that that's not the case.
Additionally, I exported the troubleshooting error log following your guide. Furthermore, I got two more crash logs, which I saved after a crash respectively. Those files were indeed too big to attach to this ticket, as you said, so I uploaded them on Dropbox. Subsequent are the links to the mentioned files:

https://www.dropbox.com/s/apiq192pi381o7o/ArmaReport_Log_20151002T210701_Rops.zip?dl=0 (troubleshooting error, 7528 KB)

https://www.dropbox.com/s/yt2s8cul177e5iy/ArmaReport_Log_20150930T200051_Rops.zip?dl=0 (I guess first crash log, 1766 KB)

https://www.dropbox.com/s/n3tg8z03yxpe0d0/ArmaReport_Log_20151001T194123_Rops.zip?dl=0 (I guess second crash log, 5294 KB)

And yes, I would love to test your experimental .exe, as long as you don't collect any too personal info.