Back button without ion-navbar

Yes and not sure .

I am not sure about the Backbutton generating thing. Like if you push to a Page so that the Backbutton generates itself. (I bet it would work out somehow but you would need to rewrite something.)

But what you can about that now:
Create a Back button where you want it and add as example following code to the button.

TS:

yourButton(){
   this.navCtrl.pop();
}

Now your Page should go back from where you pushed it .