From what I've seen, Oliveira is training hard and posting as much as he trains. But from what I've seen, his manager had said that he already had three fights lined up for Oliveira, and the first would be this one against Fiziev, so expectations for him are high and he's been training a lot.
Did he really say that he has 3 fights already lined up for him? This doesn't make much sense. Perhaps he was only talking about potential fights. The match-ups are decided by the UFC, and the choice of opponents is always heavily contingent on the result of a fighter's next fight.
As for Fiziev Vs Oliveira, both will be desperate to win as both have 3 losses in their last 5 fights. But those losses are not necessarily much to be ashamed of. For Fiziev, he lost twice to Gaethje, both times by decision and both times after giving a great show. The other loss was to Gamrot but it was due to an injury. Oliveira, in his recent fights, has only lost to the best guys (Islam and Ilia) and had one split-decision loss to Arman.
I don't know what the odds are yet, but I imagine Oliveira will be the favourite, even just by virtue of his submission skills. Bookies tend to favour younger fighters though, plus Oliveira and his team chose a horrible strategy for his last fight against Ilia, so who knows.
Basically, Oliveira's manager was asked if he would retire after his last fight, and the answer was "We have three fights pre-arranged in 2026." These were his own words in an interview ruling out any retirement.