There are two versions of customer accounts: classic and new. Both classic and new customer accounts are available to you and can be used by your customers. You can choose which version of customer accounts to use in your online store. If you choose to use new customer accounts, most links to classic customer accounts will automatically redirect to new ones.
Wholesale Pricing Now can work with both.
The important thing is that once a customer creates an account, you should be able to add the necessary Tags for them to see discounts.
For more information on the differences visit Shopify's Help Center: Customer Accounts