Is the prayer of one who missed Maghrib and prayed it after Isha' and Tarawih, then prayed Shaf and Witr, valid, knowing that the order is not obligatory at that time?

The scholars have differed regarding the obligation of observing the proper sequence (tartīb) between two prayers that share the same time when one is ignorant (of the sequence). Some have maintained that it is obligatory and a condition, and that ignorance does not waive it. Others have stated that it is waived by ignorance. According to the Shafi'is, observing the sequence is recommended, not obligatory. Some may validate a prayer in which the sequence was not observed due to ignorance, but it is preferable to repeat it as a precautionary measure and to avoid scholarly dispute.