Could black holes be creators of dark matter? At the tremendous forces of gravity inside a black hole, can "matter" be transformed into a more  degenerate form; "dark matter" (if that truly what dark matter is)?

I know the inside of a black hole isn't fully understood, but can this be an acceptable possibility? Why?
Ultra-high energetic cosmic rays are thought to be caused by black holes as one option. Those energies should be sufficient for the formation of (hypothetical) heavy supersymmetric particles, which should decay to stable (hypothetical) neutralinos, candidates for (hypothetical) WIMPS.

Assuming this theoretical framework, black holes (or similar dense objects) may cause the generation of dark matter. But the amount of dark matter formed that way won't explain the amount of dark matter needed for the Lambda-CDM model. Also dark matter forming this way should be hot (fast moving). Lambda-CDM needs cold dark matter (CDM).