Long term storage of device

I bought a BitBox02. My questions are:

1. I plan to put the device in a HSBC safe deposit box next week. I will travel soon to Australia where I intend to stay and work until September 2024. I have copied the XPUB key and, after double-checking that it is correct and 100% identical to that shown on the BitBox app and on the BitBox02 itself, imported that XPUB key into my BlueWallet app and re-verified that the receiving bitcoin address matches that shown on my BitBox app. I also saved that key in my 1Password app. I plan to add coins via this BlueWallet watch-only wallet. Is this safe or is there a potential risk of loss if I rely solely on the XPUB key and the bitcoin addresses resolved or derived from it?
2. Will the BitBox02 work after not using it for about 2 to 3 years? I ask because I remember having a phone which refused to turn on after several years of not using it. Even the battery refused to charge. Would it be wise to extract the recovery seed phrase from the device and store those words in the safe deposit box too? I worry that humidity or temperature issues (it's a bit cold inside the safe deposit box room) might degrade the internals of the device or cause the SD card to be corrupted. I know I sound paranoid but I am safeguarding 20+ BTC on it so I have to ask these questions.
3. I activated the passphrase feature. I did check and double-check by first sending a small amount before migrating my larger assets. This passphrase is stored in my 1Password app and will NOT be kept in the bank's safe deposit box. And most importantly, I would like to know if the backup file on the SD card includes the passphrase.

Would it be wise to make a copy of the SD card's contents and take it with me to Australia? Just to be on the safe side I suppose, in case something unfortunate happens to the safe deposit box while I am overseas (i.e. the bank relocates them elsewhere or in the event of fire).

Thank you and I apologise for the many convoluted questions.