You’re very close but some details slightly off…
Jackpot starts each ball at 0, and when you collect one.
Spinners (dazzler and wolverine), pops, DEADPOOL targets build value
4 shots to the u turn light colossal jackpot (also resets at ball start). Hitting the target to collect the jackpot as a combo from the u turn scores double the jackpot vs just randomly hitting the target.
Each time you shoot the u turn, whether the jackpot is lit or not, one of the 4 features (dazzler spinner, wolverine spinner, pops, or targets) will randomly be chosen to be boosted by its boost value:
Dazzler and Wolverine spinners: 20k base, 2.5k boost
Pop bumpers: 40k base, 5k boost
Deadpool targets: 80k base, 10k boost.
This boost values reset at start of ball.
Colossus Jackpot maxes at 50 million (pre-multiplier), so 100 mil if doubled, 500 mil if 5x playfield).
Technically the way it works is all these points are scored immediately, and the points resulting go into the jackpot, meaning playfield multipliers will boost the jackpot faster.
Another fun wrinkle is if you change the adjustment from MEDIUM to HARD, it changes the shots needed to light jackpot from 4 DOWN to 2. And EASY setting changes it to 6 shots. The logic being it’s easier to build a jackpot higher if it takes more shots to light it since you’re getting more things boosted without risk to accidentally collecting.