A. 2 people tie - they play one game. All clear.

B. 3 people tie - we order them by SODOS (random if not possible): P1, P2, P3. Then:
First round
P2 - P3
Second round
P1 against winner of round 1
Winner of round 2 takes the 1st place, loser of round 2 - the 2nd place, loser of round 1 - the 3rd place

C. 4 people tie - we order them by SODOS (if some players share SODOS, then random): P1, P2, P3, P4. Then:
First round
P1 - P4
P2 - P3
Second round
Winner against winner, loser against loser. The player who won round 1 and lost round 2 takes the 2nd place, the player who lost round 1 and won round 2 takes the 3rd place.

D. 5 people tie - they have the same SODOS for sure so we order them randomly: P1, P2, P3, P4, P5. Then:

First round
P1 -- bye
P2 - P5
P3 - P4

Second round
Winner of P2-P5 -- bye
P1 - winner of P3-P4 (*final)
Loser against loser (*anti-final)

Final order:
1st place - winner of the match marked as (*final)
2nd place - winner of P2-P5 in round 1 who got a bye in round 2
3rd place - loser of the match marked as (*final)
4th place - winner of the (*anti-final)
5th place - loser of the (*anti-final)