Just want to let you know that I have try out using “icgc-get” to download data from EGA and experienced the same failures as yours.
As “icgc-get” now works as a wrapper of Java-based EGA download client when downloading data from EGA, we suspect the download failures have something to do with the EGA download client. We contacted EGA helpdesk and they suggest us to switch to use the new Python-base EGA download client: https://ega-archive.org/download/downloader-quickguide-v3. I just tried the new client to download directly from EGA and it works.
So for your case, currently if the data you are interested only exist in EGA, maybe you need to use the new Python-base EGA download client to download directly from EGA. If the data also has copies in Colloaboratory or AWS, you can always use “icgc-get” to get data from other places.
We will keep you updated once the “icgc-get” switch to use the new EGA download client.
Hope this information help with your questions.