You are not alone. This is the Most difficult Boss Hunt. Even seasoned veterans, maxed out players have extreme difficulty if you dont have the right team.
1) Recommended or Ideal Team: 2 Sunflowers (MUST) 1 Peashooter and 1 Corn (or Citron)
2) During Winters Grasp (shooting the popsicle) - the team must split up into 3 groups before it begins. Peashooter on top of roof of bridge. Corn on top of hollow tree in between the divided channel. Then the two sunflowers team up near the school bus all the way in the back near the village and bridge. Corn and Peashooter while on top must keep moving because the arctic soldier will get you. Sunflowers will be mobb'd but try to heal each other. There is a nearby pot, use it, plant a pea shooter, or electro zapper. You have to do this to help control the oncoming browncoats. Each player while at this position are very close to the popsicles. There are 3 popsicles that the Peashooter can visually see on top of the roof. The Corn has view to 4 popsicles while on top of the hollow tree. And the two sunflowers have 4, I think, near the school bus.
3) After popsicle mode, all 4 team mates must re-group, stay together as one team. You have to stay alive and wait for the Jester Champion Imp to show up. If you wander by yourself, you are likely DEAD. The 2 sunflowers are KEY to survival. Alternate your heal beam to all players, constantly giving each team mate a quick health boost. The other sunflower will do the same. Finding each other quickly is critical.
4) The strongest character, Peashooter, Corn, Citron drinks the slurpee. The 2 Sunflowers must heal and top off the health of the slurpee leader.
5) During the Aura mode (Radiance) Sunflower player drops healing flower pot IN THE Circle. Avoid using Solar Beam as you cannot heal your mates. Sunflowers Only use base weapon while healing your mates. While in the circle, all shooters must aim for Yeti's Head. Head shots are critical.
5) Dont waste your time shooting at the Yeti. Shoot only during Aura / Radiance mode. Position yourself at higher ground if you can. Use the empty plant pots when you see
them, they can act as decoy or your sacrificial lamb. Brown coats will go after the potted plant, which will give you free time to aim for the popsicle.
Most of all, finding the right team is the hardest. I've seen a lot of goofy players who don't care....shooting at the tree, shooting at the generator, they dont take the game seriously as we want to. There are Players that are just playing and not so much trying to win and beat the game. Finding the players who want to win and know how to play the hunt is the hard part.
Good Luck and keep fighting.