(Stealth) Finisher completely broken

[Achimundso]

After testing things a bit in the old simulacrum I've noticed some very strange things with finishers.

Tested on a Level 165 Corrupted Heavy Gunner with a Jat Kittag, base damage = 200, 2x crit multiplier (added to show none of the "off numbers" are critical damage related); no mods equipped on anything except Dizzying Rounds on the Bronco and an unmodded Ember.

Using the Dizzying Rounds Mod for Bronco finishers sometimes deal triple damage on one hit and 50% more damage on the other (happens pretty reliably in very quick succession of bronco shot -> finisher). Both attacks from the back attack finisher deal 2400 damage, I would expect to see one hit for 800 and one for 1600.

Then there is a bug that enables stealth damage bonus sometimes as well when spawning enemies, going back to the arsenal and then moving to use finisher on the previously spawned enemies.
There is another bug that randomly deals 12.5% more damage for those stealth damage finishers, mostly only on one of two hits from finishers from the back.

Now I went on to test it with other frames.

Garuda uses her Talons for finishers even with a Jat Kittag equipped.

I equipped Vulcan Blitz on the Jat Kittag to see if it uses her modded Talons or the Jat Kittags mods and to my surprise Vulcan Blitz worked with finishers while she was still using her Talons. I tested this in regular missions too with the same bug.

Trying out things with Ash equipped with nothing but Fatal Teleport, an unmodded Jat Kittag and nothing else. Apart from the 200% Finisher Damage increase from Fatal Teleport the results are totally random. Some enemies get the 8x stealth damage, some do not. Some numbers are randomly 12.5% higher than others, some are triple damage on the first hit and 50% higher on the second hit.

Every test done alone in the simulacrum or missions, "invite only", I am the host of course.

If I find more things I'll add them later.