It should be cost 0.2$ minimum, at the best at the moment)
From Twitter: "4am! Still coding - the whole team are still here! These guys are awesome!"
if they launch a mobile wallet with mining and join the good crypto-exchange, i think - price will be about 0.4-0.5$

I don't claim to speak for Vod, but he's fair.  However, that negative feedback you got is very recent.  You might have to wait for quite a while before he'd be willing to delete it--if he does at all.  There are way too many scammers who ask for loans with scammy collateral, so that's why the negs are handed out like Halloween candy around here.  So suck it up, wait, and ask him again in a few moths, see what he says.  But keep your expectations low, because that neg might be there permanently.  And it's your fault, too.