(SPOILERS)
You're missing the "True Ending" and the "Beracus Died" ending!
To get the true ending, you'll need to think very carefully about how you proceed thru the bunker. You need to bring two items with you to the boss battle (think about what items you could keep, or maybe an item you never got? Maybe something that vanished because you did something too soon?)
And for the Beracus Died ending, it correlates with a certain item you can keep into the boss battle. <-- This one is by far the most specific and difficult, forgive me!
I hope this helps, if not I can be EVEN MORE CLEAR with how to get stuff, but I will need to contact you privately to do it ;)
Thanks so so much for checking out the game and for your lovely comment <3