[bawolff]

Sure, but we are talking about a physical theory here not a mathematical one. There are always alternative physical theories, infinitely many. They may not be good theories, but they clearly exist. This has nothing to do with cosmology but more is a fundamental principle of logic.

To put another way, there is a big difference between saying some specific alternative theory is wrong/unlikely/bad, and claiming there exists no alternative theories at all regardless of quality.