You at least have the option of legal action here in the UK
You can forget this "legal action" business.
If a school goes under (which the UK ones do regularly) you will lose your money. Litigation won't get it back because you will rank as an unsecured creditor, behind the chargeholders
In 30 years of business I have not yet seen a dividend paid to unsec creds where there was a chargeholder owed money.
If you are in the USA and are training with a school and you don't like them, you have a problem because the school's name is printed in the Visa which is stuck in your passport. There is supposed to be a process for getting this changed but it's not something you want to do in a hurry.
You won't have time to sue a school in the US. And if you did, you will be finished anyway because the next school won't take you (they don't want to be the next in line for the treatment).
You will have time to sue a school in the UK, but there isn't any point if you want to carry on flying
afterwards because you will be slagged off all over the said airport and nobody will touch you with a bargepole.