I'm sorry that you are in this situation! The pandemic is impacting so many of our normal activities.

I like my colleague's answer. I'm thinking that Dad will also be VERY concerned about protecting his child's health. It's hard to be away from loved ones, especially our kids, at this crazy time. I suggest a discussion with Dad about to balance the need to keep him and your son connected, with the CDC and State requirements that we stay in our homes for at least the next few weeks. And, however you guys resolve this issue, keep in mind that you will have the rest of your lives to be co-parents together (so try not to burn any bridges during this once-in-a-century crisis). Good luck and take care.

Contact your pediatrician and get a medical opinion. Here is my non-medical opinion: Even if the father had not gone to California he could have caught the virus as could you just going to the grocery store. I do agree that travel can increase the risk of random encounters with the virus particularly if one travels by plane and transits in airports where people are coming and going from all over. So talk to a doctor you trust and get a written copy of what the doctor recommends. You can then share it with the father and discuss it. If it does seem best to wait 14 days maybe you can arrange a virtual visit between your son and his father or better yet multiple virtual visits as a long visit via video may get too boring for a young child. I would also find and share articles with the father of young people also being hospitalized with COVID 19. The risk of a severe respiratory issue is not limited to adults. Admittedly it is less likely in young children but it does happen. Share this link with the father and look at Oregon's details which you will find if you scroll down and click on Oregon: https://www.livescience.com/coronavirus-updates-united-states.html
Here is what I am seeing as of today and it increases every day. NOTE THAT OUT OF 209 TOTAL CASES IN OREGON, 4 CASES ARE CHILDREN AGE 17 AND YOUNGER!:

Updated March 25 at 12:45 p.m. ET.

Oregon has confirmed 209 cases of COVID-19 as of Tuesday, March 24. More than 4,300 people have tested negative for the virus, and 4,559 tests have been completed, according to the state’s health department. At least 61 people are hospitalized with the virus in the state.

Four of the cases are in people ages 17 and younger, 6 are in 18- to 24-year-olds, 18 are in 25- to 34-year-olds, 72 are in 35- to 65-year-olds and 109 are in those 55 or older.

At least 14 cases are linked to the Edward C. Allworth Veteran’s Home in Lebanon, in Linn County, where half of those infected are over the age of 90, according to Oregon Live.

The state has seen eight deaths from the coronavirus. According to the Oregon Health Authority, the first individual was a 70-year-old man who died on Saturday (March 14) in Multnomah county. His was the first of two deaths in Multnomah County. The other deaths occured in Clackamas County (1), Lane County (1), Linn County (1), Marion County (1) and Washington County (2).

Oregon Live reported on Tuesday (March 24) that about 1 in 20 emergency room visits in the state are now related to COVID-19-like symptoms. While influenza case numbers are now dropping, visits to the ER for influenza-like symptoms (fever and sore throat or a cough), are on the rise, according to Oregon Health Authority data cited in the report.

Oregon Governor Kate Brown issued a statewide stay-at-home order on Monday (March 23), prohibiting citizens from congregating in public or at businesses unless for essential activities such as grocery shopping. Some playgrounds and other outdoor recreation facilities, including campgrounds, will be closed, the Lebanon Express reported.

Cases by county:

Benton: 4
Clackamas: 17
Clatsop: 1
Deschutes: 10
Douglas: 1
Grant: 1
Jackson: 3
Josephine: 1
Klamath: 1
Lane: 4
Linn: 20
Marion: 32
Multnomah: 25
Polk: 3
Umatilla: 2
Union: 1
Washington: 76
Yamhill: 6