Xbox One TES 4 Oblivion GOTY Shivering Isles Not Working

So, here's my situation.

I own the GOTY version of Oblivion, and have had no issues for years playing it on my xbox one. Now, Shivering Isles is not being recognized by Oblivion. It shows that the DLC is installed in the manage game menu, but in the in-game dlc content screen, it
doesn't register, whereas is registers Knights of the Nine, the other dlc on the GOTY edition just fine.

Here's my other issue. When I try to uninstall and reinstall Shivering Isles I am not able to install it from the manage game menu, nor the xbox store menu. It will ask me if I really want to install it, I'll press OK, but nothing else will happen. I can
only install it using the dlc disc, which acts oddly itself. Knights of the Nine, when uninstalled, will go through the normal process of installing, but Shivering will seemingly instantly install once I put the disc in.

I'm aware that you can no longer use the disc version of shivering with disc oblivion, so I bit the bullet and bought oblivion again. Except the same problem occurs, where even when installed shivering doesn't show up, and without the dlc disk Knights of
the Nine doesn't recognize either.

TLDR: I have digital purchases of both Shivering Isles and base game Oblivion, as well as physical GOTY disc. Despite having two copies, I can't play shivering isles with either.

Thank you for any assistance. I just want to do the fishstick. It's a delicate state of mind.

:)