An onlooker said Lauer was "very low-key" at the bash, which the disgraced Today alum, 65, attended to support longtime friend and honoree Jon Ledecky.
"Not morose. Just low-key," they clarified to an outlet. "He didn’t socialize much, just sat at a table."
The dad-of-three reportedly "talked to a couple of people. He seemed kind of quiet, not very effervescent. He took a couple of photos, but was by himself."
Some assumed his solo appearance meant he and Abas split, but a source claimed he told fellow attendees they were still together, and though she wanted to come out to the gala, she had "another event" to be at.
However, this is the second time the former NBC star has been flying solo in the Hamptons, as he randomly showed up to a women's luncheon at the members-only Sebonack Golf Club earlier this month.
As OK! reported, he was escorted to a private area to dine alone, with a source claiming he was there to prepare for a charity event later on.
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- 'Lurking' Matt Lauer Shows Up to Women's-Only Luncheon, Is Escorted Away to Eat Alone: Insider
- Matt Lauer Is 'a Good Man' Who Doesn't 'Miss Being On Television' After Scandal, Former 'Today' Host Bryant Gumbel Insists
Lauer and Abas — a longtime friend — first sparked dating rumors back in 2019 after he divorced the mother of his kids, Annette Roque.
An insider claimed earlier this year that the two try to keep their relationship out of the spotlight. "[They're] not interested in a high-profile life. They are off the radar and low-key," said the source. "They are enjoying their lives."
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And while some believe Lauer could get down on one knee soon, he's also hesitant to do so after his split from Roque resulted in him handing over $20 million.
"He’s paranoid he will get taken to the cleaners once more if he marries again," the source spilled. "[But] Shamin is ready to cut and run if Matt doesn’t make the commitment."
Page Six reported on Lauer's solo outing at the July 22 gala.