What I was thinking it was to force her to wear a cow uniform like how you see in many mangas and games and not transformation into a cow.
Let's imagine the dev decide to make a cow route in the farm or other place...
Since Henry told Devin to consult that doctor to see what she had and we discovered that he used hypnosis for something we don't know yet, although my guess is trying to corrupt her and her common sense of ways of dress or act to be more perverted (like thinking of being naked in front of others a normal thing), could lead to try discover why her breasts were growing and find it source.
That could develop in several ways like few ones i said. They could try make take more pills unconsciously to grow more, then train her to be more cow and then treat her as one and sell her milk for profit, etc etc and making a deal with the farmers of course.
This could progress for her milk being popular so making her breasts bigger and bigger to stock whole town, imagine whatever you want or limit.
The story could also turn in her trying to make her breasts stop growing and find the culprit but the size wouldn't go back to normal. She would have to deal with the modifications she suffered (like in taimanin asagi games where they turned her whole body an erogenous body that could cum with just the breeze of wind or cloth touching her skin and try fight against it with willpower of taimanin 24/7)
Or the path I wouldn't want but possible for a good ending was she could revert most of the modifications but not totally, leaving her with bigger than at start but not super big as the final modification. All corrupt dudes would go to jail after finding who stole her bag and made her get that humiliation.
Of course she wouldn't be the same in the end. She would have bigger breasts and still having that linger effect of perversion running her veins and still lactate but had to take some pills to prevent those urges or lactation from happening. Which means there is no way to revert 100% all bad things done to her and she suffer the effects after treatment.
This could be possible with a few routes and endings that i though as I saw this update from my own experience in playing those games or reading manga. But the imagination is infinite and all we can see is what dev will implement and how and of course what the patreons fetishes want since I bet people like me who isn't won't get much value as their suggestions. They have the money so they can influence the direction of game will take but not totally since dev makes final decision.