From the documentation
Map.addLayer(eeObject, visParams, name, shown, opacity)
Adds a given EE object to the map as a layer.
Returns the new map layer.
Arguments:
eeObject (Collection|Feature|Image|MapId): The object to
add to the map.
visParams
(FeatureVisualizationParameters|ImageVisualizationParameters,
optional): The visualization parameters. For Images and
ImageCollection, see ee.data.getMapId for valid parameters. For
Features and FeatureCollections, the only supported key is "color", as
a CSS 3.0 color string or a hex string in "RRGGBB" format.
name (String, optional): The name of the layer. Defaults to "Layer N".
shown (Boolean, optional): A flag indicating whether the layer should
be on by default.
opacity (Number, optional): The layer's opacity represented as a
number between 0 and 1. Defaults to 1.
Returns: ui.Map.Layer
I think what you want is done by parameter shown. Set it to false and the image will be added to the Map
but not displayed