Well everyone, thanks to all of your help I think this part is done:
The only thing I need to change is to "advance" the light firing a little and extend the LED wires left and right, I made them a tad too short.
Out of all of it, audio was the biggest challenge. I dumped the ISD1820 approach. I was able to de-solder the microphones and figured out how to directly load files from my system, but I just wasn't happy with the sound. I went with DFPlayerMini's which presented plenty of challenges on it's own. Per the thread here, I wound up using the DFPlayer AD_KEY_1 to set a momentary high to emulate an on-press. Works perfectly and reliably. A few pics:
The enclosure is a Goodwill Phillips subwoofer with a (very) burned out amp and 30 watt speaker. Gutted all. I used a 200 watt Pyle PLG-54 marine speaker, as this is going to be outside and exposed to moisture and this speaker will stand up.
It ain't pretty, but it all works. Here is the board with players, fog relays, and Nano all good to go. I rebuilt this board 3 times; the first I used a much smaller board and realized I'm nowhere cool enough to consider efficiency.
I used a 100 watt cheapo mono board as mentioned here. Here's a peek at the power: a 24VDC 6A PS for the amp, a 5V 500mah PS for the Arduino and related circuits, and a fuse block for the 120VAC in. Currently I'm using a 2.5 amp fuse and it's holding up nicely, if it ever blows I might bump it up to 3 or 4, but don't think I'll need to.
This has been quite a journey, it only takes a little practical experience to find out how much you don't know. Thanks again to all who assisted, now for my next project. . . . . animate the skeletons.
Plus, those regulators suck. You don't want the prop to quit on you two hours into Hallowe'en. A good buck regulator is worth its weight in peace of mind.
I think @andrewdonaldson177 copied that from ChatGPT, as he does all the time. He has several dozen answers on the forum and among them there are hardly a dozen that he wrote himself.
Another example of "good schematic" from the same author:
Not sure what your vendetta is I made the fritzing image myself after I physically put it together. The board will operate on 5 volts I have done so 100s of times. The quality of the parts used such as 7805 voltage regulator is adequet for design and development which is precisely what Arduino is for. Yes people do use Arduinos to make permanent projects. And yes there are better more expensive components out there.
Thank you I did not know that obviously. I was of the impression that since it opperates using 5 Volts that only giving it five volts would be sufficient. It probably works when I use it because I'm not running my boards for very long or the breadboard power adapter is actually putting out more than 5 volts.
Here is the board with players, fog relays, and Nano all good to go. I rebuilt this board 3 times; the first I used a much smaller board and realized I'm nowhere cool enough to consider efficiency. 
