I Need Your Opinion, Is My Friend Bullshitting?

I really don't know what to make of it, so I thought I'd post it here to get everyone's opinion.

I get on today to do my daily ritual of collecting bounties, doing the daily, blablabla boring stuff. My friend joins the party, and claims that all of his normal mode raid gear (from King's Fall) has "miraculously" turned into hard mode gear. I tell him to shut up, cause he knows I don't like raiding, but I see for myself and he actually has the harrowed gear and the emblem for completing the hard mode king's fall raid.

I tell him something's messed up, and he tells me he swears he didn't get on and that he has no clue how they got there. I check his destinytracker info, and find he didn't complete the hard mode raid, but I found that he did play the raid 20 hours ago and 18 hours ago, and I told him that. Again, he claims that the only thing that's possible is that someone hacked his account or someone just got on it and played for him. Not sure what to believe, but I find those extremely hard to believe.

I don't believe raid gear magically goes through a metamorphosis and becomes stronger, but I also don't believe just anyone can hack a server based game. I've known him my whole life, I don't know why he would lie or do the raid without me for that matter. Is there any way to confirm this?

edit: we play on xbox one, if that helps

Edit 2: he confessed, he was high as fuck