Swashbuckler panache and Gunslinger grit do not pool
Grit, luck, and panache represent three different means by which heroes can gain access to the same heroic pool, using it to accomplish fantastic feats. For characters with a mix of grit, luck, and panache, they pool the resources together into a combined pool.
PDF and text export both show pool as the second class' bonus (grit) rather than the sum of the two (panache + grit). See attached PCG and TXT for usecase.
Should be triggering the shared pool.