The moment you take Zaeed to Tuchanka after Grunt's coming of age, he actually disappears on the sly.
After some time of trying to track down his whereabouts, you discover that not only did he visit every single Krogan armory within a hundred miles at a speed that could only be described as "Santa Clausian", but within a few short hours, the story of how he survived his betrayal by Vido Santiago has already spread among the the "teenage" Krogan, who have started collectively referring to themselves as "Clan Zaeed" and have also pronounced the Angriest Mercenary In The Terminus Systems an "honorary Krogan" and "Clan Chief".
Wrex could put a stop to it and acknowledges that he probably should, but he's too busy laughing and shouting "WHERE'S THE LIE?" before giving Zaeed a commemorative bottle of Ryncol. Zaeed will later use said Ryncol to maintain his guns after he discovers that Tuchanka-made Moonshine-style Ryncol actually cleans carbon fouling and other gunk out of guns like NOTHING ELSE. For his part, Grunt insists that was Ryncol's original purpose, and nobody is sure if he's trolling or not.
Over a thousand years later, it is generally agreed by all Krogan that Zaeed Massani never actually died, per se, but rather just angrily climbed a ladder into the next world so he could beat the crap out of that one too, and his birth and death days are well-respected Krogan holidays, just like Shepard's.
