I'd assume that, if they were asked in another public method of discourse, then it'd be similar to posting something to the mainpage. Otherwise, I'd be kinda leery of posting a private matter on a public forum. Kinda like what Lana did to get the boot in the first place, ya know?
I asked for consent to discuss publicly (which I've since received). That's exactly what "If I can" means in the previous post.
(I should also note that tumblr asks are public by default and while I chose to answer them privately that was out of concern that whoever reads my tumblr doesn't care about this, not a specific request for privacy)
Anyway, having as mentioned received consent:
Lana argued that the rules do not explicitly ban sharing PMs. I rejected the appeal on the grounds that sharing PMs was only part of the violation, as well as considering it a common sense interpretation of the rules that PM sharing fails both "don't post private information" and "don't be a dick"
(I can't post the exact text of the appeal because tumblr is a terrible website and private replies to asks are not preserved in any way without third party extensions)