Maybe because if one or both have feelings for her it will be harder for her to choose and she'll end up breaking one of their hearts but idk i could be wrong
Why are the omegas in this kind of stories so bent on not telling the father who's the father? Like, if he wants to take responsibility excellent! And if he doesn't want that's also good, just say goodbye to him and that's it!
So... he started to like the uke after drinking the love potion, right? Or I didn't understand?
He had feelings from the start but I think the potion made him more aware of it.