I've made tea frequently with already vaped flower. You need to let it steep with coffee cream so there's enough fat (maybe full fat milk but I always have coffee cream). I normally make it with a chai tea blend as it is a good flavor. I let it steep for a while in a teapot covered with a cosy or towel to keep it warm. No issue feeling the effects. It will smell like weed.
I am not a chemist but from what I understand about decarb, steeping it in tea is not sufficient.