Leaving Barry out of the ending to what was already a crappy RE3 remake up to that point, was not right.
The Las Plaga were dug up in a fossilized state under Salazar’s Castle in Spain. Unless REmake 4 changes all this.Umbrella found the parasite and artificially tried to recreate it. This has nothing to do with Salazar or Spain.
Only in Spain were there viable parasites that were able to secrete spores because they were mummified. And Salazar opened access to these parasites after the collapse of Umbrella. If the corporation had access to this source, they would not have had to recreate anything, so Umbrella found the parasite elsewhere and much earlier. Since they are unlikely to have been mummified by anyone else, only fossils were found. According to the interview, the parasites were found somewhere in the wild. Personally, I suspect that this is Africa or Romania.