I'm wondering if it's hard for them to track if they don't know which bus/train I took?
That depends on where you live. If it's far from high density of cameras, they most likely won't know.
But get rid of tracking devices like, phones, some watches etc. and in high density of cameras there a lot of people, so tracking an individual one, is quite hard and time consuming.
I'd say pretend to go watch a movie. You would easily have enough time, if you're able to go alone.
Considering you're high risk they'll push on someone going with you. So maybe try to tell them you're going on a date, with someone from tinder, or something like that. and say you might be spending the night with the date.
If the date scenario is no go, say you're going for a concert with a friend, this implies limited tickets so no one from family will go, and if you name a friend you say you'll be spending the night at their place, cause party etc.
And if that's no good, try to slowly regaining their trust with small going-out from which you come back at their terms, so that they'll let you go out for longer periods of time.
