Per Arfa Daily:
That 'leaked goo' is just glue that the manufacturer has used to stick a
radial cap down to the PCB so that it 'pretends' to be an axial type....

If you are basing your belief that the cap is faulty on what you perceived
to be something that had leaked out from within, then there's a very good
chance that you are mistaken.

Ok, that cuts it. Forget about DigiKey. I'm in this way waaaaay over
my head.

Just trash these things and buy two more.
--
Pete Cresswell