For what I am reading, the library that you have installed the only thing that it asks you is that you give two classes to the element that you want to animate. I have not been able to deploy a test scenario, but presumably your code would work like this.
<?php
//var_dump($_GET);
$results = $mysqli->query("SELECT valoraciones.id, valoraciones.idUser, valoraciones.Estrellas, valoraciones.Valoracion, valoraciones.Publicada, Usuarios.IdUsuario, Usuarios.Nombre, Usuarios.Sexo FROM valoraciones, Usuarios WHERE valoraciones.idUser = Usuarios.IdUsuario AND valoraciones.Publicada = 1 ORDER BY valoraciones.id DESC LIMIT 3 ");
mysqli_set_charset("utf8");
while($res = $results->fetch_array()) {
?>
<div id="MovTesti" class="col-4" class="jackInTheBox animated"><p>TESTIMONIO</p></div>
<?php } ?>
The only thing I've done has been to add the jackInTheBox animated classes to the HTML that you put in the example, as well as to put the text within a <p>
.
EDIT
By not having more than your code I do not know if you have made a correct installation of the library, but assuming that it is the case, it should work.
EDIT 2
You could use a self-incremental variable to concatenate it to the ID and thus generate it dynamically and only:
<?php
//var_dump($_GET);
$results = $mysqli->query("SELECT valoraciones.id, valoraciones.idUser, valoraciones.Estrellas, valoraciones.Valoracion, valoraciones.Publicada, Usuarios.IdUsuario, Usuarios.Nombre, Usuarios.Sexo FROM valoraciones, Usuarios WHERE valoraciones.idUser = Usuarios.IdUsuario AND valoraciones.Publicada = 1 ORDER BY valoraciones.id DESC LIMIT 3 ");
mysqli_set_charset("utf8");
$contador = 1;
while($res = $results->fetch_array()) {
?>
<div id="MovTesti_<?php echo $contador; $contador++; ?>" class="col-4" class="jackInTheBox animated"><p>TESTIMONIO</p></div>
<?php } ?>
EDIT 3
So that the animation has a delay of 3 seconds.
$('clase_que_tienes_que_poner_a_los_elementos_que_necesitas_animar').waypoint(function(){ $('this').addClass('jackInTheBox animated delay-3s'); }