Secretly use preseed?

I want to try preseed this cycle. But I know that my fiancé will think it’s silly and won’t want to use it. He thinks all this ttc stuff (Vitex, opks, glow) is silly. He already has two kids and they “just happened”.

But I have problems conceiving so I want to try as hard as I can.

Anyway, is there any way to use preseed without him knowing? Could I put it in a different lube bottle? Or do you really need those applicators? Those will give it away for sure. And probably turn him off big time.