As to the "ticking" - my 300's have ALL experienced this when cold, but the ticking goes away after the engine warms up - typically 4-5 miles of driving. Is this not normal?
NO, it's not. My '13 had that in late 2017, thought it might be an exhaust leak since it quieted when warmed up. Was under the 5/100,000 so took it in. 5 bad rockers, all 24 replaced under warranty with an "updated" rocker arm, I have no idea what's updated about it. Not long afterwards, April 2018, I found my '16 300 with Hemi and just had to have it, so traded the '13 on the '16. Now I get the crazy noisy lifters, REALLY bad after sitting for a month, just plain bad on cold starts.
