One question I have for Delboy. Do you have at least two yubikeys linked to your Bitwarden account? This is a good idea in case you lose one (or it fails)! My wife and I both have Yubikeys and I have a third one in a safety deposit box. All three keys are linked to both accounts.
If you don’t, when you get that second key, get one with NFC.
Another possibility is a USB-C to UBS adapter. I just purchased some of these and they are cheap. Here is link to what I am talking about:
https://www.amazon.com/dp/B07BS8SRWH?psc=1&ref=ppx_yo2ov_dt_b_product_details
You can also get these adapters without the short cable but it you have protective case for your IPad, the housing might prevent complete insertion of the plug into the socket. (A lesson learned the hard way…)