While the Zamia is a slow grower, giving it good light and prescribed fertilisers can increase its growth rate. As for the Peace Lily, like any plant it will grow faster with sufficient lighting and slower in low to medium light. Although, avoid direct sunlight for both the plants
Peace Lily not flowering
The Peace lily can live comfortably in indoor space with bright to medium indirect light, but like any other flowering plant it requires a few hours of dappled sun or bright indirect sunlight for flowering.
Wilting of Zamia
Zamia is a drought resistant plant and does better with underwatering than over watering. Limp, wilting, and mushy leaves are a sign of root rot due to overwatering. If the plant is fairly erect, repot it in a drier potting mix after cutting away any part of the rot rhizome that seems rotten and water only when the soil is completely dry. If the plant is non-salvageable, take leaf or stem cuttings from healthiest stems to propagate