I don’t have any of the seasonal passes, but I was able to complete the other three seasonal prologues. It says it requires the season pass for me to run Savathûn’s Spire, but it didn’t give me this issue when I ran the first Defiant, Salvage and Riven’s Lair.
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Hello. Savathun's Spire is a seasonal activity so it can't be accessed without owning the Season of the Witch Season Pass. To have unlocked this activity, you had to play through the Way of the Witch mission.