I sugest you change line 24 of dosamigos\leaflet\layers\Layer to public $map = 'map';
This way it will work out of the box since dosamigos\leaflet\widgets\Map $name var is also defaulted to 'map'.
If you dont want to make this change, you need to at least change your example to a working one, adding 'map' => 'map' to the when creating the tileLayer.
The example posted on https://github.com/2amigos/yii2-leaflet-extension dont work.
I sugest you change line 24 of dosamigos\leaflet\layers\Layer to public $map = 'map';
This way it will work out of the box since dosamigos\leaflet\widgets\Map $name var is also defaulted to 'map'.
If you dont want to make this change, you need to at least change your example to a working one, adding 'map' => 'map' to the when creating the tileLayer.