This was news to me, as I don't hunt in the specified counties. And if the deer never sees a processor, not sure what enforcement mechanism exists, other than the honor system, and that your license log reflects where any deer was killed.
Edited to add: I don't know if a validation code is even part of the reporting requirement/result.

Discussion came up, as a local (to B-CS) processor stated he has to obtain some sort of "validation code", for the meat brought to them for processing. Details were sketchy, but researching the TX P&W site revealed:

Mandatory Harvest Reporting for White-tailed Deer
White-tailed deer harvested and tagged with a hunting license tag in the counties listed below during any open season (archery, general muzzleloader, and youth) must be reported within 24 hours of harvest via the "Texas Hunt & Fish" mobile application or online version.
Counties with mandatory buck and antlerless deer harvest reporting: Collin, Dallas, Grayson, Rockwall.

Counties with mandatory antlerless deer harvest reporting: Austin, Bastrop, Caldwell, Colorado, Comal (East of I-35), De Witt, Fayette, Goliad (North of US 59), Gonzales, Guadalupe, Hays (East of I-35), Jackson (north of US 59), Karnes, Lavaca, Lee, Travis (East of I-35), Victoria (North of US 59), Waller, Washington, Wharton (North of US 59), and Wilson.

P&W Annual
NRA Life
TSRA Life