have you verified if the https link is able to download the file?
Have you any firewall or security tool active that could block the communication?
The issue seems to be not easy. I suggest to open a PMR in order to investigate the error more deeply.
Please consider that the problem determination can be helped if they are reported details as the Site level, MDT bundle version, The Bare Metal server version, The image os type (Win7, win10 and so on), the architecture of the image if x64 or x32, if the image is cloned or if it is a setup. Or if you have noticed that the issue starting occurring after that a particular change happened in your environment.
Moreover, in these cases are required the *.trc and *.log files in the C:\Program Files\Common Files\IBM Tivoli folder of the Bare Metal server.
The error could be related to the available memory, you could even check if the free ram is reducing during the download on the bare metal server.