What he said was "I had a whole speech prepared for tonight but instead Id like to take a moment of silence for Jon Jones's brother" so, using any brain cells you may have had left, why would he not give any speech he had prepared unless it was to call out Jones? I didnt see anyone else on the card taking a moment of silence for Arthur. Plus, he's hinted moving to heavyweight.
Believe what you wanna believe but he was 100% going to call out Jones. No other reason he would have pivoted from his planned speech.