I douibt it will break it.
Actually, it is only a matter of time before it does break it. This is what happens when you install an rpm made for one system on another. A .deb has nothing to do with anything about rpms. You see, each distro can have widely different ways of setting things up. Names of dependencies can be different, or the dependencies can be in different locations. Other changes may be made.
Once you have installed from an outside source, you have made your system non-standard/unsupported. Why? There is no way for us to know what changes such an rpm made to your system.
Remember, if you use the following command, you are responsible for your own support.
rpm -Uvh full-name-andversion.rpm