You've come to a great place for advice, there are lots of people here, many of whom have had house-training challanges in one form or another.
Environment changes alone can cause a bit of upheaval and confusion for a dog - especially when there is 'training' still involved in the process and I sympathize because I know how difficult it can be to attempt to house-train at this point in the process.
As far as getting her to go on the pad on the balcony, you really need to stick to your guns because otherwise it simply won't work. She's already beat you and your wife once before as far as 'where' she wants to pee, and that is a HUGE success for a dog. The first thing I'd reccomend is crating her at night, but at this point it would take a lot of consistancy and patience to do so. She's obviously used to having her run of the place and sleeping with both of you.
If you continue to let her sleep in your bed, is there any way that you can still monitor her progress through the night? The bottom line is that unless you are able to CONSTANTLY put her outside on the pee pad where you need/want her to use the washroom, she won't learn. Sure, she may still have accidents through this process but it's entirely up to you and your wife. If you really want things to change for your dog, you may even have to get up a few times through the night and throw her outside so she can pee on the pad.
I'd also reccomend NOT putting the pee pads down in the hallway. This will just confuse her further, and lead her to believe that you aren't serious about getting her to pee outside.
This is why I encourage you to crate her, or keep her confined to a safe area when you are not home. A dog allowed to roam that has not been trained to pee outside - just simply won't.
"If you are a dog and your owner suggests that you wear a sweater. . . suggest that he wear a tail."
Vali (American Bulldog)
Artiro (Cane Corso)