Tiebreaks wouldn't matter as there would have been a blitz playoff for first place - it was the case in the women event. They would matter if more than two players share first place: while all players in shared first place would enter the playoff (change from earlier events in the open section, oddly apparently not for the women section), higher-ranked players on tiebreak get certain privileges: possible "bye" in the early stage and the playoff would be single blitz games (additional ones with colors reversed only in case of draws) with the higher-ranked player getting white. For other places, tiebreaks didn't matter financially as prize money was shared equally between tied players.
That being said as Dennis is curious: Yes, Keymer would have kept his Buchholz edge over Carlsen - reduced from 102.5-100 to 102-100.5: Keymer would get half a Buchholz point less for his game against Vachier-Lagrave, Carlsen (who didn't face MVL) would get half a point more for his game against Keymer.
The main reason for Keymer's tiebreak edge seems to be that Carlsen had two opponents who sort of collapsed after losing against the Norwegian: Jorden van Foreest had 4.5/5 before facing Carlsen to finish on 7/13. At the end of day 2, Carlsen played Quparadze - overperforming until then but unable to keep it up on day 3. BTW this easy pairing for Carlsen was thanks to Jorden van Foreest, who had lost with white against Quparadze in just 19 moves the round before. So Carlsen was somewhat lucky with his pairings at key moments.
Regarding the quick draw between Dubov and Fedoseev in the last round: Yes, the winner would have gotten a medal (Dubov apparently silver just ahead of Keymer on the second tiebreak, Fedoseev bronze), but financially spoken the loser would lose quite something with an about even risk-benefit calculation. Prize money for 2nd-4th place (shared equally) would have been 40,000$, for 4th-8th place it was 21,800$, for 9th-22nd place it was about 5,000$.
Considering their situation cautiousness is understandable? An unethical "someone wins and we then share the money" (which can never be proven, nor disproven) wouldn't have yielded much extra. It would have been a different situation, and possibly a full fight with or without prior agreements, if both had half a point less going into the final round.
Their situation: not quite world-top so few supertournament invitations. And organizers might generally boycot Russians - while both spoke up against the war and Fedoseev moved to Spain.
Maghsoodloo may have considered his game against Carlsen must-win with black (of course no guarantee that he would have drawn with solid play), while a win would have left him off the podium due to his poor Buchholz score. Dubov and Fedossev also already have world rapid champpionship medals: Dubov gold in 2018, Fedoseev silver in 2017.
Tiebreaks wouldn't matter as there would have been a blitz playoff for first place - it was the case in the women event. They would matter if more than two players share first place: while all players in shared first place would enter the playoff (change from earlier events in the open section, oddly apparently not for the women section), higher-ranked players on tiebreak get certain privileges: possible "bye" in the early stage and the playoff would be single blitz games (additional ones with colors reversed only in case of draws) with the higher-ranked player getting white. For other places, tiebreaks didn't matter financially as prize money was shared equally between tied players.
That being said as Dennis is curious: Yes, Keymer would have kept his Buchholz edge over Carlsen - reduced from 102.5-100 to 102-100.5: Keymer would get half a Buchholz point less for his game against Vachier-Lagrave, Carlsen (who didn't face MVL) would get half a point more for his game against Keymer.
The main reason for Keymer's tiebreak edge seems to be that Carlsen had two opponents who sort of collapsed after losing against the Norwegian: Jorden van Foreest had 4.5/5 before facing Carlsen to finish on 7/13. At the end of day 2, Carlsen played Quparadze - overperforming until then but unable to keep it up on day 3. BTW this easy pairing for Carlsen was thanks to Jorden van Foreest, who had lost with white against Quparadze in just 19 moves the round before. So Carlsen was somewhat lucky with his pairings at key moments.
Regarding the quick draw between Dubov and Fedoseev in the last round: Yes, the winner would have gotten a medal (Dubov apparently silver just ahead of Keymer on the second tiebreak, Fedoseev bronze), but financially spoken the loser would lose quite something with an about even risk-benefit calculation. Prize money for 2nd-4th place (shared equally) would have been 40,000$, for 4th-8th place it was 21,800$, for 9th-22nd place it was about 5,000$.
Considering their situation cautiousness is understandable? An unethical "someone wins and we then share the money" (which can never be proven, nor disproven) wouldn't have yielded much extra. It would have been a different situation, and possibly a full fight with or without prior agreements, if both had half a point less going into the final round.
Their situation: not quite world-top so few supertournament invitations. And organizers might generally boycot Russians - while both spoke up against the war and Fedoseev moved to Spain.
Maghsoodloo may have considered his game against Carlsen must-win with black (of course no guarantee that he would have drawn with solid play), while a win would have left him off the podium due to his poor Buchholz score. Dubov and Fedossev also already have world rapid champpionship medals: Dubov gold in 2018, Fedoseev silver in 2017.