A friend had this in her Advent calendar and found it so great that I thought - I have to test it!
Actually, no vanilla detectable. In the opening, it is very floral with a fresh plum note. When the plums are not quite ripe yet and you pick one and break it open to remove the pit, that scent comes through in the opening alongside the floral notes.
Additionally, there is an alcoholic scent that doesn't go in any specific direction. A bit like a glasses cleaning cloth, I would say, light but noticeable.
After about 4 hours, the sweetness comes, from vanilla? I don't know. When you walk past Primark, a sweet plastic scent wafts out of the store, just like back in the day with cheap Barbies, and that's exactly how it smells now.
Fortunately, it has no sillage, so you can only smell it when you hold your nose close. It's really quite terrible. Longevity more than 7 hours.
Are you sure your sample wasn't spoiled, or maybe it just wasn't the right fragrance? Your description doesn't match at all with how I know and perceive it! I can clearly smell vanilla, and it's not alcoholic at all.