I would not trust that combo at all, while I know very little about Pims I do they are rather predatory, much better odds than a lottery ticket that at some point it will try and eat a Corydoras. Which will then lock out its pectoral and dorsal first rays and release poison, then both die (unless you somehow rescue the Corydora fromt eh Pictus' mouth/throat.
Brochis would be far safer, most Hoplo-esque Catfish might be fine depending upon the Pictus' ID, Callichthys would certainly be up to the task. But then a group of Pictus will need a fair bit of space, ideally in something 5-foot or more.