Agreed, the explanation is simple speculation/conjecture. Frankly I can't understand NASA's motivation. Just announcing that this is a very interesting anomaly

Agreed, the explanation is simple speculation/conjecture. Frankly I can't understand NASA's motivation. Just announcing that this is a very interesting anomaly and further investigation is required to identify it properly, surely plays in their favor (think, political support / funding.) Instead, we get a weak, non-specific speculative press release, that as you say, is devoid of any mention of further study/investigation.