There may be many reasons why Ma and Shao did not appear in the CCTV World Cup. First of all, they may not have been selected as the commentator of this World Cup, so they can't appear in CCTV's live broadcast. Secondly, they may not participate in the commentary of this World Cup because of personal affairs or other reasons.

Please note that this is only a possible explanation, and the specific reason may need more in-depth understanding and investigation.