Impossible to complete "Living Legend"

[Former user]

I was playing as ecolog faction. After gathering documents from agroprom faction and bringing them to the barkeeper, he told me to go meet a stalker called Cerberus (or whatever he's called in english) at the army warehouses. Immediately after that, the quest was updated and "failed", leaving me with a broken save and unable to progress further. RIP. https://i.imgur.com/b5UkMzc.png

[STALKER Anomaly]

Please attach (if available) latest save before this happened (.scoc and .scop files for that save), so that we can try to reproduce the issue

[STALKER Anomaly]

Removing version: Anomaly 1.5.0 Beta 3 Hotfix 1 (automated comment)

[STALKER Anomaly]

Incomplete bug report, requested information still missing