Interfering with a 911 phone call is a Class A misdemeanor and is a person crime. As such, it carries a maximum punishment of 1 year in jail and a fine of $6250. In Jackson County, it rarely is charged as "domestic violence" because it rarely involves violence. If it is charged as constituting domestic violence, the State would have to prove those elements of the crime but it would mean that your daughter's father would be facing the loss of his right to own firearms.
Most of the time, the consequences are closer to community service and unsupervised probation but cases differ. I would strongly suggest consulting an attorney on the matter. If the person has nothing else on their record, they would be able to seek expungement (deletion) of their record 3 years after their date of conviction - if they end up convicted.
You also have important rights under the Oregon Constitution that could be enforced with counsel or through an advocate - be careful, though, as these folks are often in favor of prosecution and may view you as someone who does not know what is best for you. Good luck to you!