Well, most endings didn't happen you know. The only ones that did happen are the whole tie between Reptile, Nitara, Cyrax. Blaze is unconfirmed. Frost's ending happened. Umm... Scorpion's happened. Li Mei's happened. I can't remember if any other ones did. Mavado's, I think, bu then he died.

im pretty sure mavados didnt happen and kano is dead so not sure whos ending that is.

Actually, its not right to say who's ending for sure happend. In Frost's ending, she freezes herself to death, I think, but she's comming back in Armageddon. As well did alot of people die in some of those endings that you claim to be true, but would it really make since to say all of these people who dies miraculously came back because someone brought them back for Armageddon?

As for the endings, I didn't like most of them. They were all cliffhangers that were never answered, such as Scorpion's ending, Drhamin's and Blaze's (which we will probably find out in Armageddon). If those endings weren't going to even be canon, then they should have at least made them the rest of the way up.

The canon endings are:
Scorpion (except he manages to escape before being ripped apart)
Li Mei (but she is rescued)
Frost (except that the Deadly Alliance wasn't beaten)
I think I read that Kitana's ending happens, but BEFORE they fight the Deadly Alliance, I'm not sure...
Reptile (See Sindel's MK:D ending which most likely means that Cyrax and Nitara's endings happened)

Non-canon:
Kung Lao
Sub-Zero
Sonya
Johnny Cage
Raiden
Bo' Rai Cho
Kano
Shang Tsung
Quan Chi
and many others...

Unconfirmed:
Mavado
Hsu Hao
Jax

Kitana's ending never happened, because Goro ended up being alive, so there was no burial.
And I didn't mean Mavado's ending happened, but he did mess up Kenshi.

I think Mavado, Jax and Hsu Hao's endings happened, as there's nothing so far to say that they didn't. Here's how I think they happened.

We already know Mavado takes Kenshi down, so for his promised reward, he gets the fight with Kano. Again he wins, and Quan Chi recruits the Red Dragon on his side, giving them the mission to kill Shang Tsung, who he suspects of betraying him. Mavado passes this mission onto Hsu Hao (as we see in Hsu Hao's ending) who heads for Shang Tsungs palace, but runs into Jax, who kills him. Jax then joins his friends in the fight against the Deadly Alliance, which happens inside Shang's palace. Sometime either during or after the big fight, Mavado is beaten, likely killed by Kabal.

If Hsu Hao had lived a little longer, I think he'd have probably laid low during the fight, then come out afterwards to help Quan Chi kill Shang Tsung.

Mind you since MKA is bringing everyone back, and with MK's history of retconning things, there's a chance they may throw this out of the window and give another explanation.