Can I keep raw meet thanks to fermented veggies?

This is a tip someone gave, but if I can check out the reliability....

So I have tried to put some raw beef in a jar with a commercial ecological sauerkraut.
I have kept it with NO FRIDGE from sunday to friday.
It looked "cooked" and I could eat it raw with no problem. Very good in a salad...
Each time I eat some, I cut the outside that was in contact with the juice, and I put back the rest in the glass jar with sauerkraut.

I have done it again and in the end (like 5 days) I had to give the meat to the cats because it did not look and smell so good.
Of course I cannot control the age of the meat when I buy it, the size of the piece is not the same each time, the quantity of cabbage or juice in the jar, etc.

I did not write the experiment, and sometimes I have put some thyme essential oil in the jar... It might help...

What do you think, what can be the risk? Is the nose enough to check out?
Is the meat fermenting itself like this?

Oops, I cannot edit to change "meet" for "meat" in the title!!

While reading other posts, I begin to think that yes, the sauerkraut makes the meat ferment as well.

I make a little "up", if Sandor did not see the post and can help with some ideas for making it properly.
I am concerned with the time I can keep it, how long?

I also had the feeling that the meat was ok, but not the juice, after some days.
Is it possible that the meat is OK because is it under the juice?
And the juice is going bad because it contains some meat particles ABOVE (floating), and so in contact with air?