No, she is using [d], not [ɾ], because you can hear a brief friction ([z]-like sound) after /d/, which doesn't occur with [ɾ]. But she is pronouncing the 'n part as [ən], not [n̩] like many other people do. [ən] and [n̩] are interchangeable in this position (see
this Wikipedia section for more).
As for your last question, yes. In North American English, /d(ə)n/ preceded by a vowel as in wouldn't, couldn't, didn't, etc. can be pronounced [dn̩], [dən], or [ɾən]. My impression is that [dn̩] (with a nasal release) is most common, followed by [ɾən] and then [dən]. But there is a fair amount of variation among speakers—and even within a single speaker: you can hear her use [dn̩] here right before the sentence in question—so you probably need not worry so much about it so long as you can produce at least one of the three options.