Yes, Google ad manager will work if Adsense account would be disabled, because google ad is something different than google ad sense.
Publisher can continue using Google Ad Manager even if they’ve lost their AdSense account.
Google Ad Exchange (AdX) is a different story. I’ve seen publishers banned from AdSense while using GAM and still be able to run Ad demand. However, you are more likely than not going to have your account disabled across both platforms (AdX and AdSense) and could face issues receiving payment for AdX.
