On PS4 I have never gotten the savior schnapps to actually work for me. It says it was a successful save weather I use it through the menu or the save game option but when I die it says: load failed and I am forced to use the previous save.
Edit: After some research I read you can only have 3 savior schnapps at a time (I somehow had 4) so I dropped one and saved and IT WORKED! however now all other saves FAIL no matter how many I have (sleeping, quest saves, etc…) and it reverts back to my one, and only, savior schnapps save, losing hours of gameplay in the process. (It doesn’t help that I’m trying to complete the Nest of Vipers quest.)
I used the savior shnapps just as I got into the building in the rear of the cuman camp before lighting the arrows on fire and escaping the camp. After that I saved (sleeping) no less than three times. Afterwards I went back to Sir Radzig and continued the quest and got killed by Runt after which the “save fails” and I’m back in the cuman camp.