There are some messages about your problem in the forums of the Kayako community. Did you try to find them or contact Kayako support?
The odds are against that, since "Kayako" and "support" are no longer a "thing".
They sold it to a venture capitalist and basically eliminated the download version with absurd prices and total negligence.
As for the pipeline, as a temporary solution, you can switch to the polling of the email account through POP. If the pipeline is failing in Namecheap, it is in them, not in the Kayako software. I know that in some suppliers in the past we had to enclose the path of the pipe in quotes while we set it up to work. I've never received anything with NC, so I'm not sure of them.