Did my test last night with probe under husk.
Preparation: Peel husk back, remove as much silk as will come off easily, fold husk back on, soak in water (important), tie ends, place in steamer for 12 - 15 minutes depending on size. Steam temperature was 203°, corn temp under husk at 14 minutes was 197°. Result was as usual, very hot, moist and tender.
Note: Any remaining silk after steaming, can easily be removed by wiping corn with dry towel.