RECONNAISSANCE DE DIPLOME MAITRE NAGEUR ET ENTRAINEUR.

First bit of advice - If you want to go to England, use English.
(More people will understand you.)

Second. Why isn't it worth anything in England? The only real reason for that would be it's some bit of paper from some pretend establishment, not a real place.

Anyone that asks you for money to çheck'you out is a scammer or just a rip off.
Are you sure your English is up to scratch because the ASA site

http://www.swimming.org/asa/teaching-an … -or-coach/

says,

How much does the initial qualification cost?

Typically around £390, but don't let lack of funds stand in the way. There are bursaries and grants available which vary according to location but some even pay 100% of the course costs.

Anyway, use/learn English and you'll probably stand a better chance.
Google, that mysterious and almost impossible thing to use, will get you that information in a minute or less.
To me, that lack of ability to perform a simple task, your posting in the wrong language and your qualification being questionable, suggest you aren't suitable to supervise kids in a potentially dangerous situation.