Could describe what you wish in a bit more details?
Now, when a requester replies, the status is changed to "In progress" automatically. Do you want to check whether the requester has an "End-User" role and change the status from "In progress" to "Reply from customer" after adding another comment from the requester?
Do you mean that a newly created ticket should have undefined (empty) status?
It's very strange. Please provide me with screenshots of a "Ticket Statuses" list (all items values in "Name" and "Internal Name" columns should be visible) and a newly created ticket to see its current status and the whole history of changes (a tab inside ticket).
Please follow these steps:
Create a custom status on the "Ticket Statuses" list (you can find in "Site contents").
Set a condition. The comment should not be initial ([Comment.IsInitial] equals to false) and its author should have got the "End-User" role ([Comment.From.Role] equals to 'End-User'). Comments are stored on a "Comment" list. The "From" field of which has a lookup data type and refers to a "Contacts" list which has the "Role" field. And to that field, the [Comment.From.Role] refers.