Okay, so, how about this: What if Snow resisted the manipulation, but was magically coerced into spilling the beans. When Snow confesses, she's clearly distraught about telling(because from her end, she has no idea why she went from upholding her promise to spilling the beans in seconds), causing Regina to ask for enough details to recognize the magic that was at work. Same result, but allows Regina to accept it wasn't really Snow's fault.
(and fwiw, I do take issue with Leopold -- his characterization is pretty odd, ranging from declaring that he wants everyone in his kingdom to be happy to reading his wife's diary and being pretty open about not caring about her. The only interpretation I can think of that unites the two aspects is that when he asked for the guy he thought Regina loved to be brought to him, it was to tell the guy he was fine with the queen having someone on the side if it made her happy, just to keep it quiet 'cause that sort of thing tends to look bad.)
no subject
(and fwiw, I do take issue with Leopold -- his characterization is pretty odd, ranging from declaring that he wants everyone in his kingdom to be happy to reading his wife's diary and being pretty open about not caring about her. The only interpretation I can think of that unites the two aspects is that when he asked for the guy he thought Regina loved to be brought to him, it was to tell the guy he was fine with the queen having someone on the side if it made her happy, just to keep it quiet 'cause that sort of thing tends to look bad.)