I assume MWO is referring to the multiverse idea?

yes.

As I understand it the mathematics works, but there is no positive evidence for it either.

the funny thing about math is, it works in theory.

we can prove mathematically that the projectile will always hit its target

we can prove mathematically that light and radio waves can make it from one end of the universe to the other.

and, with just a little slight of hand, we can prove over unity devices actually exist.

these are important points to remember.

"in theory" or "according to the math", doesn't have a one to one correlation to reality.

the mandelbrot set of fractals are another example.

we can solve its equations and plot points all day long, but a mandelbrot fractal can never exist in reality.

One idea is that our universe was 'birthed' from another universe, . . .

Another idea is based off of 'if string theory is true' (notice the "if"), . . .

here again. we start with pre existing conditions.

we must start with exactly nothing

One interesting thing about the probability of abiogenesis, well not exactly abiogenesis but related, is the Fermi paradox. In summary the galaxy is so old with so many stars/planets that could house life that we should expect the entire galaxy to be seeded with intelligent life, even if there was only one intelligent civilization that mastered interstellar travel to a level that we can reasonable conceive of based on our understanding of physics and engineering. However, we have no verifiable empirical evidence that aliens exist. People have proposed various solutions to the paradox ranging from the fact that we've only really been able to search in a small section of the galaxy to aliens have already visited Earth in the past or even now undetected. How it relates to abiogenesis is that one proposed solution is that despite all the potential planets out there, abiogenesis (or multi-cellular life, or intelligent life) is so high a barrier that it is essentially a fluke that any planet has life at all. Just thought you might find that interesting.

another problem is that all of our efforts to contact these beings will most likely fail, simply because of the vast amount of time it takes for signals to traverse the distance.

unless a civilization is very close, we have no hope of contacting them.

all of our efforts hasn't even left our own galaxy yet.