Did a run in which I got over 19,000 points afterwards, I realized the audio was not being recorded... RIP. Anyways, at >=9000 Points, Brutus (Green Guy) will start teleporting on top of the player upon every movement leading to an eventual game over. What follows is the strategy I've discovered to achieve an indefinite highscore amount.

1: Get as close to 9000 points as you can. You must not go over 9000 points!

2: Wait until the maximum of 4 hearts are on screen and grabbable.

3: Use spinach to kill Brutus (Green Guy) on repeat. You can kill him twice with one spinach, but it is possible to kill him three times with one. While you are doing this, make sure to grab as many hearts as possible. This still has a good amount of RNG dependency, since during this if Brutus (Green Guy) is ever alive while you are not, say in "Spinach Mode" you will die over and over leading to a Game Over. It can be very annoying and hard to do because the spinach likes to bounce from the left and right side at seemingly random intervals, making it sometimes impossible to continue the chain of killing Brutus (Green Guy).

4: Keep doing this until the score will roll over to the ten-thousands digit. So, a score of 0100 would actually be 10,100 points. From here, gameplay precedes back to normal. Then repeat these steps for as long as you can.

Good luck!