The pick appears to make sense; as the article points out, Washington (18-0-1, 12 KO) was already training to appear on the card and shares a similar build. Wawrzyk is 6’5" and weighed in at 240.5 pounds his last time out, while the 6’6" Washington weighed in at 243.75 for his knockout of Ray Austin.
The Austin win was Washington’s second since a grievously boring draw with Amir Mansour in 2015.
This would be a definite step up rankings-wise, as the WBC has Washington at #10 to Wawrzyk’s #12, and would most likely be a more competitive fight. Wilder (37-0, 36 KO) should still win by monster knockout, of course, but he may actually have to work for it.