Only vets can be avian certified, not the hospital. A diplomate (the US certification) is a veterinarian who has done extra study and exams and published journal papers and is a specialist in the field. Only people with this certification in Avian Health are allowed to call themselves avian specialists. However, many many veterinarians are competent Avian veterinarians but haven't done the board exam to become a diplomate of the american association of veterinarians. These vets are allowed to call themselves bird vets or vets with a special interest in bird medicine but NOT allowed to call themselves specialists.
The best way to find if your vet is at all competent with birds is to check and see if they are a member of the Association of Avian Veterinarians (aav.org). There is a link to the Australasian site through this webpage for all those Southern Hemisphere peeps

. Most good bird vets are members of this association (or the Aussie one) and will attend regular meeting and do continuing education. However, of course there will still be dubious people that join these groups so word of mouth and recommendations from other bird owners are also invaluable.
Diplomates will have extra letters after the vet qualification (which is DVM or VMD in the USA). These letters will be something along the lines of dABVP (Avian health) or something similar. These vets can call themselves avian specialists. There are also qualifications from Europe and Down South here in New Zealand/Australia - but we use different letters

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It is very tragic that this has happened to this poor little quaker

. I urge you all to find a certified avian specialist or a non-certified but recommended avian vet in your area and take your birds to these people. Vet schools don't teach much avian medicine so the extra study and an interest in the field is mandatory for vets to be competent avian veterinarians.