It says "
Uruviel has the game text" but you only heal when "at" a sanctuary (not when you can spot a sanctuary). Therefore, unless the fellowship is "at" Uruviel, they can't heal.
EDIT: Also, cards that spot forests spot "forest sites," so they wouldn't be affected by Uruviel being a forest, either. The only exceptions are
Galadriel, SotHL, which says "forest on the adventure path" (but Uruviel isn't on the adventure path) and some Fellowship Block cards (
Natural Cover,
Voice of Nimrodel, &
Legolas, SoT) that require being "at" a forest (but the fellowship isn't "at" Uruviel). So while Uruviel being a forest is weird, it doesn't affect gameplay.