Shisheannaith19
You might be trying to call the contact center from abroad, in this case try +41 51 225 78 56
For the luggage transfer, you’d basically need for each person a public transport ticket from Zinal to Zermatt, even though you’re hiking a (cool!) alternate route…
Depending on the group size, you might want to check with one of your accomodations whether they can arrange something, using a vehicle licensed to drive into (car-free) Zermatt.