Damian didn't want it to be known that he had sabotaged Angela or got in her way, as that would tarnish his reputation and might ruin his chance of becoming the next family head. However, he knew that if he wanted something to be done, he needed to do it himself and was willing to risk it to stop Angela from stealing the position that he had worked towards his entire life.
Even if he couldn't stop Angela, Damian could still form the alliance with the Epstein Family before they could and knew that he couldn't directly engage in combat with neither of them as Wayde would be able to easily defeat him, along with the Epstein Family.
Martha didn't say anything and did exactly as Damian instructed her to do, as she prepared herself and Damian with many charms, including disguising charms that would be very useful for them to conceal their identity.