I would suggest to clarify the situation you ask the relevant persons where you have seen the certificates for a look at it. Examine it and see whom issued and exactly what it is. I very much doubt, if not totally doubt, that it was issued under the FPA Act. The old Social Services used to register Care premises, amongst others, and it may be cert of some sort under that.
It might be that a premises was used as a hotel etc and then changed hands to form a care establishment. If they did not notify the Fire Authority then unless the Brigade inspected, in Scotland Hotels are usually annually, it may be an old exoired cert.
Hey some people even make up their own in a similar format to convine/confuse etc but I very much doubt that.
To sum up I would recontact and ask for clarification.