Prior to 2019, I accumulated a significant number of MAID and stored them in Bitcoin-QT wallets on a desktop computer, assuming that I could access these coins whenever the network went live. Since that time, my old Bitcoin-QT client stopped working and I subsequently upgraded to version 22 on my mac. I moved one of my old wallet.dat backups to the ~/Library/Application Support/Bitcoin folder; however, none of my old bitcoin addresses holding MAID or BTC shows up as addresses in my wallet (I tried rescanning and a number of other methods, but to no avail). First off, if I still have these wallet.dat backups, can I stop panicking, knowing that eventually I will find my MAID coins? Next, can someone please tell me how I can restore my wallets from 2018 so that I can begin converting my MAID coins for the new coins? Thank you in advance for your assistance. I will be forever indebted to you if you can help me!
As long as those wallet.dat files relate to the same wallets you held MAID on, then yes, you should be able to get them back again.
Have you tried using Electrum, or another wallet other than Bitcoin-QT?
Remember you will not see MAID in a bitcoin wallet, you will need an Omi-qt client. If you have the bitcoin one then you can grab the private key and get to your coins in omniwallet. Plenty here will help, I am not into all that, but many here are really well versed in all the nuances.
First scan your old bitcoin address in omniexplorer.info to find where are your Maid.
When you find the address with the Maid, you can export the private key with the order
dumpprivkey [bitcoin address].
Next, you can Import this private key in omniwallet.org to proceed to the Maid-ANT conversion.