Igor and Zina a couple?

[Zorah]

I am not sure of where this question best belongs. I'll leave it here, with gratitude for anyone who can help a newbie out.

I am on my 6th book about the DPI. Two of these books have stated that Igor and Zina were interested in each other, this latest one (L.Anderson's) states directly that "she [Zina] and Igor had been dating for months." Am I missing something? Are people going by her photo being in his possession and letting their imaginations go wild? Or is there real evidence that they were a couple? (Like, say, statements from friends at UPI). I wish authors would be clear about their sources.
Like, don't even get me STARTED about catt dahman and her 'hypoxia at ten thousand feet above sea level'....OMG