I read USCIS is currently running its services in a limited capacity. You might be able to file the papers through them, but what is happening at the port of entry is not known to me. People are still flying around I guess as I heard flights are still running but very low in number.
Technically they are allowed to enter, but what is going on at POE is not very clear. Please ask anybody who have just flown in to the country recently. This is uncertain especially now when some people have died in Nepal as well and the officers at POE might be taking note of that.