Just wanted to post a followup to this post and sincerely thank everyone for their assistance.
I ended up taking everyone's advice and bought a Delkin 128GB CFexpress card and reader. Our 16 day trip to Egypt and Jordan was a target rich environment so I captured thousands of pics which I now have to cull and prepare. My upgrade from my old D7500 to the D500 proved to be a fantastic upgrade.When traveling I use a Tamron 18-400 but took a 35mm 1.8 for inside the tombs, but only used it once because of the close proximity.
Here is the final solution based on all of your advice. I preloaded my Sandisk 2TB Extreme Pro SSD with my standard file structure for each day of the trip. When shooting, I only recorded images onto the CF Express card but kept a 256 GB Sandisk Extreme Pro SD Card in its slot. At the end of the day, in camera, I copied all files on the CF Express card onto the SD Card, exchanging, locking, and storing the SD Card when it was approaching full. I then removed the CF Card and put it the card reader, then, using an iPad Pro and hub, copied the files on the CFexpress Card onto the appropriate day folder on the SSD. After verifying that all images were on the SSD, I reinserted the CFexpress Card into the camera, popped out the SD card for safety, and reformatted the CFexpress card to start the next day fresh. That gave me copies on two formats while on the road, then when I got home, I put another copy on my iCloud Drive and back up HD at home.
The system worked very well, but one day, I found that all the images on the CFexpress card had not copied over to the SSD drive or the SD card. The verification step caught the discrepancy, and I went back and copied the missing files. Not sure what caused it, but it proved that all steps were necessary for these once in a lifetime pics.