Looking at the last 50 English wiktionary blocks at http://en.wiktionary.org/w/index.php?title=Special%3ALog&type=block&user=&page= I see that the longest blocks were 4 one year blocks: 2 open proxies and 2 external link spammers.
Looking at contributions of infinite account blocks at http://en.wiktionary.org/wiki/Special:Ipblocklist of non sock accounts, where the edit wasn't deleted, I see only http://en.wiktionary.org/w/index.php?title=maxim&diff=prev&oldid=3462092. That no warnings were given simply means that the wikt admins are trying to create a dictionary instead of playing whack-a-mole with the obvious vandalizing only accounts and spammers. OTRS is there for any bad blocks.
If the ORS tickets (all emails sent to info-en@wiktionary.org) were for really bad vandals, then there isn't a problem. Looking thru the queue for open block tickets, there's ticket 2007122410005487 where the IP didn't get an infinite block as claimed, but 1 day; and ticket 2007121710004036 about an entry deleted by 3 different admins because it's obviously spam and not a dictionary entry.
Please provide some diffs which resulted in incorrect infinite blocks. The wiktionarians, stewards, or foundation can then look into it.