That fear turned to dread when more than two years passed with no sign of him.
Then, the unbelievable happened. On Wednesday night, while Hoffman was on Facebook, a picture caught her eye. It included two cats, one of whom was her long-lost tuxedo, Sid. Judging from the posting, he was alive and well in another family's care in Cherry Hill.
A reunion came two days later in the home where Sid had become Ansel Catems.
"I would have dreams that we've found him, and then to actually find him, it's like a dream come true," Hoffman, 25, said Sunday. "To be able to hold a pet that you've believed had died is a very weird feeling."
Linda Rosenson Coe, 55, has been taking care of Sid since September 2011 - while making many efforts to find his original family.
"I knew he had to belong to somebody, but I could never find that somebody," Coe said. "I never would have kept him without making every effort to find his owners."
How Sid got to Coe involved an intermediary with two dogs that probably would not have been thrilled with the idea of a feline brother.
Denise VanHorn found Sid in her backyard in Blackwood after Hurricane Irene blew through. The cat was about a mile from home.
VanHorn said she wanted to help the animal find a safe home. Her two dogs - a Cavapoo and a Lhasa apso - made it untenable for hers to be that home, she said.
So she took Sid to Coe, with whom she once worked in continuing care.
"I care about every animal under the sun," VanHorn said.
As does Coe. She had recently adopted another cat, Chloe, from the Animal Welfare Association (AWA) in Voorhees.
Coe had posted a picture of her new baby on Facebook that also happened to include Ansel Catems in repose with his new sibling.
That's the picture Hoffman saw Wednesday night. The AWA had shared it on Facebook, and Hoffman is a friend of AWA's Facebook page.
"I knew the second I saw his picture that it was him," Hoffman said of her Sid. "There was no doubt in my mind."
That was confirmed when she finally got to see him in the fur and flesh.
"He's very quirky. The way he would walk, the way he would play," she said. "It's the same boy."
If you think this uplifting story ends with the cat happily back home in Blackwood, you're mistaken.
Hoffman decided the best course of action was to let him stay with Coe and her husband, Marvin, a photographer and fan of Ansel Adams.
"It was really the right thing to do," Hoffman said. "Taking him away would have confused him, and it would have been hard for their family, and they are great people."
A grateful Coe said: "This is just the best outcome we could have imagined in what has really been a very heartbreaking situation for another family. I'm so happy they are pleased with how we are taking care of their beloved pet."
Hoffman says she will stay in touch with the Coes and might make occasional visits to play with the cat they all adore.
"They love him, and he's alive and happy, and that's all that matters," Hoffman said. "It was the best possible outcome for a bad scenario."