If this young person cannot handle so simple a negotiation as being walked down the aisle on her wedding day, then she is in no way ready or fit for marriage, and is not about to enter into a true marriage, and both her parents have a morale obligation to (1) Communicate that fact to her, and (2) If they can’t successfully communicate that fact to her to withdraw their material support for what will be a sham marriage.
This is the one issue in this young woman that we’re aware of because she graciously posted her side of things in public social media. I’m sure that the parents are aware of the other 43 issues that we’re not a party to.
I don't think that was a gracious posting. It looks to me that she is an "influencer", and was posting to her TikTok channel, complaining about her parents for fun and profit.
I have seen the same procedure many times, and the young women are always putting on makeup while they complain about something.