When it comes to Echinopsis huascha/Trichocereus grandiflorus it is almost impossible to know if you have the true species or not - In all likelihood the one with the white flowers is not - as E. huascha/T. grandiflorus as a true species has red flowers as far as I am aware.
The red one could be straight up E. huascha/T. grandiflorus, but in all likelihood it is also a hybrid as most of the plants sold through the big box stores under the label E. huascha/T. grandiflorus are hybrids these days. So unless you can trace your plant's heritage to a plant that was collected in nature (and the collector's name and collection number are available) and propagated from it through offsets/cuttings you have to assume that it is in all likelihood a hybrid.
I often see them labeled as T. grandiflorus hybrid, which I think would mean that in the database it's name would be. E. huascha hybrid - if there is an entry for hybrids where one parent is known. None of these big box store plants come with a cultivar name as far as I am aware, so E. huascha hybrid would be the closest you could come.
The plant should not be posted under E. huascha, because that would imply you know that it is the true species. I can already see that there is a picture in the database under E. huascha that most likely is not a true huascha...
