Greetings! Muscovy ducks can be a good addition to your flock, however, their behavior can be quite different from that of chickens. It's important to ensure that you provide ample space for both ducks and chickens to roam around, as well as different areas for each species to retreat to.
As for introducing muscovy ducks to your two white campbells, it is important to introduce them slowly and monitor the situation closely. Ideally, it's best to keep your new ducks quarantined for a few weeks before introducing them to your existing flock in order to ensure they're healthy and free from diseases.
When it comes to socializing, ducks and chickens can get along, but it's not a given. Some chickens may be intimidated by the larger size of ducks, while ducks may be too aggressive with smaller chickens. It's important to supervise their interactions until they've settled into their new social hierarchy.
Overall, adding ducks to your flock can be a fun and rewarding experience, but it's important to do your research ahead of time and take the necessary precautions to ensure that everyone gets along.