1. I believe you are referring to only vedana due to physical touch.
This is where sukha, dukkha, and adukkhamasukha vedana arise. Examples are sleeping on a soft bed, an injury, and touching the body. In the first case, one may get attached via sukha vedana, and in the second case, via dukkha vedana.
Getting attached to an adukkhamasukha vedana with that definition is subtle. One example could be the following: You are sleeping and are awakened by the whole house being shaken by an Earthquake. You get scared.
2. In the strict sense, the sensory inputs via the other four physical senses (sights, sounds, tastes, smells) only cause adukkhamasukha vedana.
Therefore, the initial sensory contact with sights, sounds, tastes, and smells only leads to adukkhamasukha vedana in the strict sense. They are the common cases of getting attached to adukkhamasukha vedana.
But in many cases (in the suttas), somanassa may be included in sukha vedana, and domanassa may be included in dukkha vedana. That is because “mind-made vedana” also lead to attachment, and no distinction is made. But it is good to clarify and understand the usage.