The score says how it ended. xG says how it should have ended: it is the sum of the chances each shot was worth, not an opinion about the game.
The score matched the game: Orenburg was the better side by chances too.
Orenburg: −4.3 for the season (11 in the table). Rostov: −1.6 (12). The gap between points and xPTS is built from matches like this one.