I think you could try sprinkling the earth with baking powder to see if that will soak up any excess water, and absorb the smell. It shouldn't harm your plant, I'd have hoped. Worth a try before you throw your your plant.
I've come back from holiday and the house stinks. I've tracked it down to a very large pot plant, I think it's the compost/ soil. The plant is much too big and heavy for me to repot it! Any ideas or shall I just throw it away?