Sadly, no, I have not. They are both very rare, the Short-tailed Bat extremely-so, and they are both very tiny. I have tried to see Long-tailed Bats in two places in NZ but no luck so far. I have seen the Short-tailed Bat in captivity though, when they were on display at Auckland Zoo a few years back.
What was their exhibit like at the zoo? Do they have a nocturnal hall? I assume as insectivorous bats that they were difficult to keep in captivity for long?
They were in the nocturnal house (if you imagine an enclosure for a kiwi, they had one like that). Short-tailed Bats forage terrestrially on the forest floor so in captivity they can be fed from a dish.