She would be considered a qualifying student as long as she was in school for at least 5 months in 2019. Even if she received no 1098-T.
So, if she graduated May of 2019 or later, then you can still use her as a full time student to qualify as a dependent for the other dependent credit as long as she lived with you at least one month after graduation (because you need to live with someone at least six months of the year to claim as a dependent and time away at school counts toward the six months).