What makes you think not? He already segregated them so if he hears about them conspiring against the Leaf he may act swiftly
The relationship between the Uchiha and Konoha weren't on bad terms (enough to stage a coupe) until
after Tobirama died as the rumors started after Obito's siege on Konoha.
Tobirama isn't an idiot. There's very few Uchiha who would have the prowess to attack the 4th, steal the Jinchuriki away and Control Kurama. He would immediately believe "
Madara Uchiha" is alive. This is the same conclusion that Minato came to. He didn't suspect the Uchiha, he suspected "
Madara".
Unfortunately, Minato's death, Kushina's death and Kurama having giant sharinagn pupils
made it damn near impossible give the Uchiha the benefit of doubt. Literally all witnesses died and Obito got away scott free. Had Tobirama been alive he would have went to where he buried him and realized that old fart was still alive.
He'd have no reason to go after the Uchiha if they're already being policed. Tobirama feared another Madara and in his own hubris inadvertent had a hand in almost creating another one (Sasuke Uchiha) due to BZ orchestrating everything.
