I poured very hot milchig soup into an empty eino ben yomo meat bowl.  Then after washing it out I got it mixed up with another bowl that looks just like it.

So now we have 2 bowls sitting secluded and I don’t know which is which. Rebbe said we might be saved by a sfeik sfeika.

Thank you so much and good yom tov!

According to the Rema1)YD 94:5 and Shach 2)93:3 the bowl is treated as treif since it has bliyos of both meat and dairy. We can’t use it until kashered. 

Now that it is mixed the din is that it can be batel b’rov 3) as per S.A. Yoreh De’ah 102:3 . After more thought I don’t know any other eitzah but to kasher the bowl since you don’t have rov kosher bowls against the treif one. 

In this case you actually have to kasher both bowls.

References   [ + ]

1. YD 94:5
2. 93:3
3. as per S.A. Yoreh De’ah 102:3