Carpet Runner Installation - Opinions

We had carpet runners installed on our main and basement staircases by a company. For reference they completed both staircases within 1.5 hours. I am not sure if this is standard.

The basement staircase is largely okay, however, we are having issues with our main staircase. Specifically the binding looks wavy/dimpled from where the staples were placed. See photo: https://imgur.com/a/DwvOTNj

We have some other issues with our main staircase, however they seem to be addressed by the company. The waving/dimpling however was not. We had their manager come out and look at the runner and he is adamant that all the runners he installs look this way - and that it's normal for this type of carpet (wool). I am just wondering if this is the case. I am not very familiar with this type of work and don't know whether to take his word at face value or push back (if it can be improved).

Any opinions/suggestions would help so I can know whether we should leave it as is, have them re-do it, or get another company to take a look/do it themselves.

Thanks!