The result leaves Warriors and Perpignan locked at the top of Pool 2 on 15 points, but with the French team narrowly in the driving seat.
If two teams finish on the same number of points, top spot will be firstly decided by who has earned the most number of match points from the two matches. Currently Worcester and Perpignan have four points each.
After that the team that has scored the most tries in the two matches go top - and Perpignan lead 3-1.
"We are going to have to hope that Bizkaia Gernika RT or Femi-CZ VEA Rovigo play well enough against Perpignan to deny them a try bonus point," admitted Hill.
"It's not in our hands now; if Perpignan beat the other teams with a try bonus point then they will go through.
"However, strange things can happen and maybe Rovigo or Gernika will do enough against Perpignan.
"We have just got to look after ourselves in our two remaining games, make sure we get the bonus point and do all we can do to get the maximum ten points and see where we end up."
Meanwhile, Hill revealed he was confident the injury suffered by captain Dean Schofield was not too serious. Schofield was forced off with an ankle injury after half an hour at Stade Aime Giral.
"Dean is not too bad. He couldn't put any weight on his ankle, but I don't think it is too serious," said Hill.
"It was a very bruising game, huge amount of effort and the lads are quite sore, but in a funny way I think they have taken a step forward today.
"To come here and play like we did, it's a huge confidence boost and we played a lot of rugby and kept the ball in hand," added Hill.
"We played some terrific rugby at times and created chances, with a bit more accuracy we would have come away with more tries.
"I'm disappointed we lost, but to come here and get a bonus point in the manner we did, we have taken a step forward and the group is growing in confidence."