Well to avoid retaliation through a defimation suit, a person should make sure that no one can prove that it was you who alerted the press.
In other words. Get a VPN to hide your IP address, get a new email address that does not link back to you.
You must get the email address using a VPN, and at this point u can do two things at least.
Contact an investigative reporter to back round check the situation and background check the mashgichim.
Or using your new email address and a VPN, get a new ywn username and say which pasach program it is but do not give any other info at all, as that will in able them to show it was u and Sue you.
I would just say name the program and where it is. Do not indicate through Grammer that u are the one from this post.
Now I would suggest that you contact an investigative reporter instead of just naming the place as. Through one people will more readily believe u, while just naming the place is not as believable and people might think your just a disgruntled worker and will not heed your warning.