OK, so one thing i have learned while doing this instance is most of my mythic 9 and lower strats don't work so well anymore. You need to endure rather than burst mobs down due to the high hp. It is almost as if you need lust for every boss. so ill go through each boss real fast and share my experience.

Hymdall: I wiped on this boss 3 times before getting him down. Strat is the same but he actually killed my pets at a decent rate which caused me to gain agro. I FD and he dropped the swirly axe of death on my face. Other attempts were just me failing at not getting hit by the tornadoes. Insta death from one of those. Overall not so bad.

Hyrja: Hardest boss by far. I had to change my strat completely to beat her. Normally you burst her on lightning side and all is good. You cant make it through the lightning phase and the arcing bolts anymore. You just die...so i moved to other side and spread my characters. Kept the boss a good distance away from the hunters and prayed for the best. Took me 3 attempts with new strat to get her down with everything popped. Expel light does about 1/3 of my hp which regens really fast on the chars with legendary legs. Sanctify dmg is even less than that and you have a fair chance when spread to not get hit.

Fenryr: Easiest encounter but still wiped one time. You need to spread for this. FD the adds off you for 2nd phase and when he does his scent of blood mechanic i followed on all and popped cheetah to get away. Once done spread again and kill.

God-King Skovald: 2nd easiest fight. No lust needed. Just follow mechanics with the shield and kill adds. His fellblaze rush ability is dangerous but look for it and when he begins the cast disengage immediately or say goodbye to 75% of your hp. Make this a priority over dps. Wiped twice on this boss.

Odyn: Easy fight no lust needed. 100% mechanics. #1 kill adds as soon as they spawn. #2 don't get hit by glowing balls of death. #3 Move out of spear of light when he casts it under you. other than those 3 items i have no fear on this fight. I pick up the rune on my main character only if it is close to me. I don't go out of my way to get it. Just keep bursting he will die. Worse part about this fight is you can't Brez. But its fairly easy to avoid the dmg he does. By the time you get to rune phase the encounter should be nearly over.

I'm curious how you handled Odyn symbol mechanics. Judging by the missed timer I'm guessing no?

This is what has put me off to 5 boxing again this expansion. I just can't see doing well under these circumstances. But I am going to start tank + heal some mythic+ instances real soon!
Don't let this discourage you. This is all new territory for me. There are no guides to look at to see what can be done on each fight at mythic 10+. I bet if i had another +10 key i could get damn close to beating the timer knowing what i know now. Tyrannical is a beast of an affix I just needed to adjust. adapt and relearn everything I thought I knew for every boss.

Any other questions post em up!