Display Discount Prices For Customers Coming From Specific Url

Hello guys,

is there any way to display discounted prices fo customers that are coming/forwarded from a different site?

For example, if customer X visits a shop they will see normal prices but then customer Y which has been forwarded to the shop from website Y will see discounted prices.

The URL from website Y can include a specific cookie or a token to let the cs-cart know that those are special customers allowed get the discount.

I have checked the Promotions but there is no way to add conditions like the above.

Or maybe is there a way to temporarily assign customers to a specific user group with a discount without creating an account?

I will appreciate any help.