I believe the pressure component of the Perique process (~30-50 psi) serves to disrupt the cell walls of the lamina, releasing the leaf enzymes into the oozing liquid. Perhaps (read, "I don't really know...") you might be able to initially crush the leaf at the required pressure, then allow the leaf-goo brew to ferment without pressure for several months. The formal process releases the continuous pressure only infrequently (say 3 or 4 times over 9 months), so I suspect that the egress and ingress of the goo into the leaf may not be essential to the outcome. Adding water may not be the way to go, since the high osmolarity (high concentration of compounds) of the goo inhibits undesirable microbial growth in a manner similar to jellies and jams.
Bob