you must fill out Form 5329 for 2016 to show what did (not) happen. There is a penalty tax imposed for this.

You may on the form request the IRS to waive part or all of that tax. attach a statement explaining your "reasonable cause" for missing that RMD.

Note: as of this writing Turbotax makes this difficult without a 1099-R to work with. you'd have to invent one, or prepare the form 5329 yourself.