Friend’s African Dwarf Frog missing web front hand?

Can you ask your friend is the frog was always like this, or if after they added it to their tank, it lost it's webbed aspect on it's hand? If anything I'd watch for signs of the infection that you noted, since it's very very common and can lead to a loss of an arm/leg (and then be fatal). I'd also ask if they have any fish in the tank, or other decorations that might have caused for it to loose it over time (such as that SpongeBob Krusty Krab decoration in the photo if the individual webbed hands were caught in multiple times and ripped).