The NASA ASRS is not an anonymous blog. This system has been in place for decades to allow air crews, controllers, maintenance personnel to file a written report of events that happen in aircraft in flight, preparing for flight or after landing. NASA analysts review them for patterns which might affect aviation safety. Then they make periodic reports and recommendations.

The intent and purpose of this is to permit truthful, candid reports of events that happen during air operations without fear of an enforcement action. It requires a written report and a receipt is mailed to the originator with a date stamp. It must be sent within 10 days of the event and is anonymized after NASA receives it.

This is precisely the type of event this system is supposed to be used for.

Now, as for whomever placed that tape over an oxygen mask door which is supposed to deploy when there is an unexpected rapid cabin depressurization has done several things:
1. They have disabled an essential safety mechanism, rendering the aircraft unairworthy.
2. They have performed maintenance on an aircraft likely not having in their possession an Airframe and Powerplant rating granted by the FAA authorizing them to perform maintenance on an airframe, thus rendering the aircraft unairworthy until it is inspected by an Airframe mechanic with an Inspection Authorization.
3. They have potentially place the life of an occupant of the lav at risk, and thus you are correct. A formal report should be made to the local Flight Standards District Office and the airline's Primary Maintenance Inspector to determine who authorized an unrated mechanic to make changes to the airframe not in compliance with the manufacturer's maintenance manuals or contrary to FAA AC-43 on a certificated airplane.

The FSDO should make all effort to find the guilty parties and haul their sorry butts before the local administrative law judge and fine the snot out of them. Or get the FBI involved. Tampering with an aircraft is a federal offense and does come under the FBI's jurisdiction.

And maybe the airlines should hire off duty FFDOs to guard the airplanes while on the ground against anyone who might wish to climb on pitoh/static systems, flight control surfaces, or tamper with aircraft equipment. Or pilots might just decide to write up a maintenance squawk stating the aircraft was tampered with and ground the plane until maintenance goes over the entire aircraft. A few of these, particularly if they depart DCA when congress is leaving might get someone's attention.