Sadly you can't.
There is 21 day window between them deactivating the account and when their submissions are deleted where you can download them.
Sometimes they can deactivate their account and leave their submissions up, but this is rare.
In this case its been more than 21 days and they have left their submissions up/
I suggest trying the wayback machine, though its likely an incomplete archive, especially if there are any NSFW content.

But it worked before. Why not now?

AtomicTEM already explained what is happening here. What is hard to understand?
Contrary to that old corollary about the Internet, where everything stays allegedly forever, the Internet is actually very ephemeral.

Should I give you a ballpark figure of the amount of sites/blogs/profiles etc. I've missed in the last years? Just for olden and golden Tumblr (sigh) alone?

Funny thing is all of the images on Tumblr that were "purged" are still there, if you have a direct link to a "purged" image you can see it and download it, in its full HD quality. So if a tumblr was deactivated or deleted etc, but you use the wayback machine, look up the old profile rick click open the image in a new tab, remove the part of the URL that is the wayback machine, boom original image. now sometimes the url will have 480 at the end, change it to 1280 or some other higher resolution if there was one and boom, full quality orignal image :D

@AtomicTEM I mean this.
#6015

[urllib3.connectionpool][debug] https://www.deviantart.com:443 "GET /api/v1/oauth2/deviation/535394FB-825D-5A67-4980-6BCC70704DDA HTTP/1.1" 200 1290
[urllib3.connectionpool][debug] https://www.deviantart.com:443 "GET /api/v1/oauth2/deviation/metadata?deviationids%5B0%5D=535394FB-825D-5A67-4980-6BCC70704DDA&mature_content=true HTTP/1.1" 200 455
[deviantart][warning] Unable to access premium content (type: watchers)
[urllib3.connectionpool][debug] https://www.deviantart.com:443 "GET /api/v1/oauth2/gallery/97F08EAB-FC84-CB71-57C5-A9C5C827B34B?username=cerebrictech&offset=0&limit=24&mature_content=true&mode=newest HTTP/1.1" 400 101
[deviantart][debug] {"error":"invalid_request","error_description":"Account is inactive.","error_code":1,"status":"error"}
[deviantart][error] API responded with 400 Bad Request
[deviantart][error] Unexpected API response: {'error': 'invalid_request', 'error_description': 'Account is inactive.', 'error_code': 1, 'status': 'error'}
[deviantart][error] An unexpected error occurred: KeyError - '535394FB-825D-5A67-4980-6BCC70704DDA'. Please run gallery-dl again with the --verbose flag, copy its output and report this issue on https://github.com/mikf/gallery-dl/issues . [deviantart][debug]
Traceback (most recent call last):
  File "gallery_dl\job.pyc", line 151, in run
  File "gallery_dl\extractor\deviantart.pyc", line 152, in items
  File "gallery_dl\extractor\deviantart.pyc", line 729, in _fetch_premium
KeyError: '535394FB-825D-5A67-4980-6BCC70704DDA'

So the issue I have here isn't that the file isn't downloadable, it's that when you hit one of these the extraction is cancelled, refusing to download past that. Or at least that's what seems to be happening when I run into the issue. Am I just being extremely unlucky in running into folk with this issue as the last item to download?

[urllib3.connectionpool][debug] https://www.deviantart.com:443 "GET /api/v1/oauth2/deviation/535394FB-825D-5A67-4980-6BCC70704DDA HTTP/1.1" 200 1290
[urllib3.connectionpool][debug] https://www.deviantart.com:443 "GET /api/v1/oauth2/deviation/metadata?deviationids%5B0%5D=535394FB-825D-5A67-4980-6BCC70704DDA&mature_content=true HTTP/1.1" 200 455
[deviantart][warning] Unable to access premium content (type: watchers)
[urllib3.connectionpool][debug] https://www.deviantart.com:443 "GET /api/v1/oauth2/gallery/97F08EAB-FC84-CB71-57C5-A9C5C827B34B?username=cerebrictech&offset=0&limit=24&mature_content=true&mode=newest HTTP/1.1" 400 101
[deviantart][debug] {"error":"invalid_request","error_description":"Account is inactive.","error_code":1,"status":"error"}
[deviantart][error] API responded with 400 Bad Request
[deviantart][error] Unexpected API response: {'error': 'invalid_request', 'error_description': 'Account is inactive.', 'error_code': 1, 'status': 'error'}
[deviantart][error] An unexpected error occurred: KeyError - '535394FB-825D-5A67-4980-6BCC70704DDA'. Please run gallery-dl again with the --verbose flag, copy its output and report this issue on https://github.com/mikf/gallery-dl/issues . [deviantart][debug]
Traceback (most recent call last):
  File "gallery_dl\job.pyc", line 151, in run
  File "gallery_dl\extractor\deviantart.pyc", line 152, in items
  File "gallery_dl\extractor\deviantart.pyc", line 729, in _fetch_premium
KeyError: '535394FB-825D-5A67-4980-6BCC70704DDA'

So the issue I have here isn't that the file isn't downloadable, it's that when you hit one of these the extraction is cancelled, refusing to download past that. Or at least that's what seems to be happening when I run into the issue. Am I just being extremely unlucky in running into folk with this issue as the last item to download?

Did you find a solution?