I recently purhcased a Brown Scapular at the request of a visionary named Jack Marie Smith (who has a bishop's letter approving him)...
The fact that Jack Marie Smith promotes the false Marian apparitions at Conyers, Georgia and at Garabandal, I would not trust him.
The fact that he makes himself public by doing speaking engagements and having a website where he talks about himself, I would not trust him either - humility is always displayed by those who actually did see the Blessed Virgin and Our Lord. They did not want the limelight, and actually preferred to have their apparitions kept private and not revealed.
There are currently over 215 people claiming that they are are receiving messages from the Blessed Virgin or our Lord. Either they are liars and are seeking attention or money, or are hallucinating from mental imbalance, or else the devil is appearing to them under appearance of Jesus and Mary. Satan always tries to lead people away from true revelations by false ones.
One should always reserve judgment on claimed private revelation to persons until the Church has made a full investigation and decreed that it is worthy of belief.