It seems a lot of people are making uninformed assumptions that will likely age badly. First and foremost, Ime said, "All guys, if healthy, are eligible to play." I guess one could posit that not being vaccinated might be considered, 'unhealthy', but that seems a stretch.
Tatum and Rob were both confirmed as getting the vaccine by several articles. It's obvious why Rob missed the game, as he had just torn his meniscus the night before.
Horford just recently said, "I'll be ready to play wherever." I suppose it means he hasn't yet been vaccinated, but it at least insinuates that he will get it if needed.
That leaves Brown. But by all accounts he has previously praised the vaccination efforts of the league:
https://twitter.com/JaredWeissNBA/status/1446590132635701248/photo/1 Isn't it quite possible that he is just being diplomatic in his role as VP?
It should also be noted that there was a team dinner in Toronto that Josh Richardson and Dennis Schroder did not attend, but everybody else did. This was the first game against them in November. The rules at the time allowed unvaccinated individuals to play, but they had to remain in their hotel rooms the rest of the time. No way Jaylen and Al would have been out to a team dinner in public unless they were actively breaking protocol.
It's entirely possible the team is lying by releasing these details about guys being vaccinated, but I am going to choose to believe that the team is standing by their response at the beginning of the year about not commenting on vaccination status. It seems as though Ime slipped up, but that should be considered a good thing for people still worried.