My only guess is they have a parallel skunkworks working on the same thing, but in a way that they can keep it closed-source - that this was a hedge they think they no longer need, and they are missing the forest for the trees on the benefits of cross-pollination and open source ethos to their business.
But management at AMD should be above petty team politics and fund both because at the company level they do not care which solution wins in the end.
Good enough CUDA + New feature x gives them leverage in the inevitable court battle(S) and patten sharing agreement that everyone wants to see.
AMD' already stuck its toe in the water: new CPU's with their AI cores built in. If you can get a AM5 socket to run with 196 gigs, that's a large (all be it slow) model you can run.