Unfortunately, Shopify doesn't let us combine discounts, so Wholesaler doesn't work with discounts yet.
This isn't generally a problem: wholesalers already have a discount, so you usually don't want to apply another one on top of that! Also, Wholesaler won't interfere in any way with retail customers so you don't have to worry about them.
However there comes a time where you want to have a discount for wholesalers too. What to do with that? Use the bulk update with CSV feature provided by Wholesaler. This will allow you to update prices for the selected products/variants during the selected sales period. So scenario will be: a Wholesaler will still have his usual discount + you will have temporarily modified some product prices to match with your temporary pricing needs. It is a bit manual, but it will help you give that extra push to them during special times. Let's close the sale! We have faced so many merchants use this trick for Christmas, Black Friday or Cyber Monday booms.
With that said, we are working very hard every day to try and improve Wholesaler based on your feedback and this one is on our radar as some of you have requested it, so stay tuned because in the near future it might be possible to offer discounts easily for your wholesalers!