Vaya es algo raro, pero creo que el problema esta en que haces una llamada a Mial desde el callback, prueba reorganizando el código a algo como:
Código PHP:
Ver originalMail::send('emails.budget', $budget, function($emial) use ($data) {
$email->from($data['emails']['customer']['email'], $data['emails']['customer']['name']);
$email->to($data['emails']['sales']['email'], $data['emails']['sales']['name'])->subject(tran('email.subject'));
$email->attach($data['img']['file'], ['as' => $data['img']['name'], 'mime' => $data['img']['mime']]);
});
Mail::send('emails.budget', $budget, function ($email) use ($data) { $email->from($data['emails']['sales']['email'], $data['emails']['sales']['name']);
$email->to($data['emails']['customer']['email'], $data['emails']['customer']['name'])->subject(trans('email.subject'));
$email->attach($data['img']['file'], ['as' => $data['img']['name'], $data['img']['mime']]);
}