Hello, and welcome to Just Answer.
In looking for information on Blackstone, I've located an article regarding a class action suit against them based on securities fraud. The article is HERE.
I would be extremely careful with ANY so-called investment company. One thing you might try is contacting the attorney general's office in the state of any such company. They will have information on known fraudulent companies.
The Florida Attorney General's Fraud Hotline is here: 1-866-966-7226
The main website is HERE, and it shows lots of information regarding fraud, especially targeted at older Americans.
I hope this helps, but please let me know if you have more questions regarding this.
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