$membersadmin = json_decode(file_get_contents("https://api.vk.com/method/groups.getMembers?group_id={$groupId}&count=100&filter=managers&access_token={$tokenadmin}"),true);
htmlspecialchars($membersadmin['response']['users'][0]['id'])
foreach($membersadmin['response']['users'] as $user) {
$adminIds[] = $user['id'];
}
# $adminIds - нумерованный массив айдишников