I'm sure you'll find the Sattel instructors fine, especially if you can speak a little German in case of lost-in-translation issues.
We have found over time in our ski school in Engelberg (Prime Ski School - see sig) that many English-only learners, particularly adults, do get on better with native English speakers, perhaps just because it makes them feel less challenged. The fact that your instructor is of a similar background and possibly (like my wife and me) also learned to ski as an adult can sometimes reduce the pressure on nervous beginners.
So do check if they have any native speakers and try to get them if possible.
Otherwise, of course I'd recommend coming and skiing with us in Engelberg
Don't be put off by its reputation as an advanced skiers' resort - yes, it is, but it also has great facilities for beginners, even at the village level. It's really only for intermediate skiers that the terrain can be a little more limiting.