Hi Tasha, welcome aboard. I had a look at the medal rolls for the Queen's South Africa Medal and there are almost three pages of De Villiers's but none with initials L or V. It was often problematic for men of Afrikaans ancestry who served in British forces so many such men never claimed medals and in many cases their was never any request/return completed for their medals.
I take it that that his place of birth was Wynberg in the Cape? If he hadn't actually left the Cape and become a burgher of the OFS or ZAR then if he served with Boer forces he would have done so as a Cape Rebel. You might be able to find his name in the database of the Anglo-Boer War Museum which has a searchable database for Boer forces:
www.anglo-boer.co.za/database-search/
Best of luck,
Mark