Need serious help on what to do next. We are staring down the barrel of a TPK and I need to know the best route from here.

Party WAS 5 lvl 10 characters 1 path of the giant barbarian 1 barb/paladin mutliclass 1 twilight cleric 1 sorcerer/warlock multiclass 1 fighter/ barbarian multiclass.

So players have been fighting Karazikar for the last couple sessions (shorter plus dinner)

Currently I've,

Disintegrated 1 permanently (barb/fighter) Killed 2 with death rays (barb/paladin and cleric) (technically 3 but the cleric revivefied the paladin then I hit her and then him again)

Luckily my sisters 1st pc from the start is here as a slave and she rolled for her to show up so they have a lvl 8 druid (missing and arm) who just came back but has the lvl 4 exhaustion.

Currently Karazikar has retreated up into his personal chambers and is low on health (last 50ish) with a new modron (wild magic from fazrezz made it appear) shedrak was just killed so its just Karazikar but he is essentially untouchable right now since the only one who could reach him is the sorcerer with fly and all he has to do is look at her and she's powerless.

I know a couple ways they could do things to help their chances but its still a crap shoot about how this ends.

So currently here's my "options" I feel I have/plans I need help with.

1) it was all a dream, amd pull back to the last rest before the fight. I could do this in a couple ways. A) I've had this idea since the start as a way to pull back from a tpk and just have them role madness B) It be from the Fraz Urblue gem and him doing it and using this as a way to urge them to release him so he can "help" C) while slightly different I could pull all the way back to gravenhollow as 1 pc l Tried to peer into the future to see the outcome. I could have this be "one of those he saw"

2) Devine intervention. Either through the killing of karazikar and just getting them through it or some type of resetting event A) Have Jim Jar be the one to reset it. The players are already on to him as a God kinda. One tried to look at his true being in gravenhollow and I pulled a cass from supernatural and burned one of his eyes out. So this could work as a get out of jail free card 1 time. B) have it be the cleric, or warlocks diety/patron who saves them.

3) They helped themselves they just didn't know it. A) this would be where it just rests with 0 explanation. My idea is that it won't be explained until they go to the maze engine and during that fight I just fudge some rolls or what not and have the maze engine "correct the hardest moment in the groups life" or what not. Its a little loose and if they get into worse trouble later on its hard to explain but if done right could be great payoff in the end.

4) dues ex machina. A) the group has 5 fully grown hook horrors, a red dragon wyrmling, and 1 adult basilisk from the first half that are pets. They've been cared for trained and raised by our loving friend stool besides the 1 sorry 2 left from the original escapes. (who has also grown up) and the party left them at guantelgrym. I could have them show up in a rage because (insert bs reason here) and come to save the day. B) prince derendil is an elven prince (I know I changed it) who when back to get people but hasn't caught up, Asha is also a friend even though she isn't with them currently. I could have them show up somehow and help out.

Honestly at this point any other help or ideas are appreciated and I could use any and all input on the options I presented plus any other you have to suggest.

Please please help me. I've killed and torn apart the group so much worse than I thought I would. Like I knew after the first beholder at lvl 8 that petrified 3 (the same 3 dead now) that I needed to be careful but they are all 2 levels higher now so I m thought they would be ok. But the environment with the bridges has just wrecked them in a way that while I knew would be an issue... was way stronger and devastating than I anticipated... also not to be mean but they haven't exactly been.... "smart" imo.. but as the dm its easy to see and know what is and isn't so I know that could/is unfair to say.