This museum has probably moved about 400 north into the LAC Lugano Arte e Cultura building.

This is now a construction zone. Signposts for rcn 77 and ncn 5 cycling routes seem to have been removed partially, but I could not find a diversion signposted on 21-May-2018. This may need a survey in some time after the construction has finished.

Two Case Cana's on the map very closeby.
node/5625085944
node/5113086243
Are they really both named like this, or is there a mistake?

According to the official GPX the Alta Via no. 2 is crossing in between these buildings somewhere, so there must be a path or footway, but this is invisible from the Imagery. Local survey is needed to determine where this path is, or if the Alta Via no. 2 is going somewhere else.