Dark energy is an unknown thing that CAUSES the acceleration of the expansion of the universe. I think you have cause and effect backwards.
EDIT: it would appear, by the way, that you are attempting to "think outside the box" on this which is a good thing in general, but surely you understand that it is foolish to try to think outside the box when you don't yet understand what is IN the box?
Another thing to be careful about is theorizing just based on wordplay. Sometimes people use the term "the fabric of space" figuratively, but if you take that literally and say, "well space is a 'fabric' and fabrics have elasticity therefore space must have elasticity", then all you've really done is manipulate words in order to support an assertion that is unfounded. In reality, modern physics does have things to say about the properties of empty space, and those theories about empty space are pertinent to dark energy and how it behaves. But it is important to use those theories as a starting point, without resorting to analogy.
If we'll reify the equations, yes dark energy is negative pressure that is causing the expansion of the universe.
Dark energy is the Lambda in the Lambda-CDM cosmological model. Dark energy as well as dark matter balance the equations in similar way that coefficients and delta balance the chemical reaction equation satisfying the conservation of matter and energy. But unlike the chemical equations that is relatively easy to validate in the lab, cosmological equations is difficult. http://en.wikipedia.org/wiki/Lambda-CDM_model