FWIW, at Vigil practice today, we were informed by Father that attending tonight does indeed fulfill the Obligation.
It had been explained to me in an earlier RCIA class that the liturgical day actually begins at 5 pm the evening before. That's why Saturday evening Mass has the liturgy for that coming Sunday, and why Saturday evening Masses don't begin before 5.
In most cases what I bolded is true, although there are exceptions ..... tonight is one big exception, obviously. So is Christmas (different readings at the Vigil, at Midnight, and for the Mass during the day).
But in the law there is no requirement that you have to hear a particular set of readings.
All it says is you must attend:
1) anywhere in a Catholic rite
2) on the day of the feast, or on the evening before.
If you have any doubt on that you can check the link on the Vatican website I linked above.
sure seems like this reply answered your concerns...which seemed to do with the different sets of readings... did it not?