Megrara quest does not progress

[Gasdrubal]

Need advise - for some reason my Megara quest does not progress to the scenes in Zagius room, so I can not open the stage where I will present Abrosia though I think I did all prerequizits (I'm on 14th level of pact, kiiled her and her sisters many times, also on increased boss fight difficuly. Can not understand what I can do to progress relationship with her

[Tiank]

From Hades Gamepedia:

After a random number of encounters with the Furies, Megaera will approach Zagreus in his room, and tell him that she's only stopping him from escaping because she has to. (This requires her to have first been in his room to collect her belongings.) After this interaction, Megaera can receive Ambrosia the next time she is met in the House of Hades.

It is NOT necessary to enable the "Extreme Measures" condition of the Pact of Punishment.

So as you can see, you should just keep playing. Some events trigger randomly after some runs and there is no way to force them to happen earlier, unfortunately.

[Jun Gling]

All you can is to do more and more runs until you roll required dialogue. As for when it actually happens i can't tell you because it's completely random. Also it does not have any EM requirements as far as i know. Only prerequisite for progressing Meg quest is her spawning in Zag room to collect her stuff, and even after that it can take a while.