Must one make up the 'Asr, Maghrib, and 'Isha prayers if some yellowish discharge (kudrah) preceded the menstrual period, then blood appeared, and it is not known whether the yellowish discharge was continuous during the times of those prayers or not?

The relied-upon opinion with us is that yellowish or brownish discharge is not considered menstruation unless it occurs during the accustomed period or is continuous with blood after it. What you see of brownish discharge preceding the blood is not considered menstruation unless it falls within the duration of your accustomed period. If it was within the duration of your accustomed period, then your prayer is not valid, and you are not required to make up for it. However, if the brownish discharge was outside the time of your accustomed period, then you have the ruling of a pure woman until you see blood. Since you slept and do not know the exact time the blood descended, the default is to attribute it to the earliest possible time. Therefore, you must make up the aforementioned prayers after your menstruation ends.