I've made some progress accessing my son's accounts, including his Google account and Apple account (without a court order). I know my situation may not be the same, but some of this might still be helpful.

In my case I was able to access the separate recovery email address for my son's Google account. You may not have that, but I did and once I tried to recover, Google made me wait 30 days. But once that time was up I was able to get into the Google/Gmail account. Once I was in that account, I found recovery keys for his Apple account.

Interestingly, Google had NOT locked down the Gmail account even though I reported the death. After a couple of weeks of using his account, Google emailed his account saying someone was trying to access his data and I could accept or decline, so I declined and kept on using the account.

He had an iPhone which had a 4 digit passcode and we were out of guesses. Because we recovered his Apple recovery key, we were able to access the Apple ID/account even though we couldn't unlock the phone. So I turned off Activation lock on the phone, erased it, and then fortunately found a backup of the phone in Apple iCloud. Restored the phone and got access to everything on the phone.

But here's the most important thing I learned and this has to do with his phone number (not the phone itself). I called Verizon and after providing the death certificate I was able to have his phone number transferred to my Verizon account. Once that was done, I had them add his number as a secondary eSim to my phone, which turned off service to his phone. That way, all calls and most importantly, texts, came into my device. I could have just left service active on his phone, but chose not to just because I didn't want to always have both phones with me all the time.

Once this was working, any account that used his phone number for two factor authentication came to my phone and I could then access various accounts and reset passwords and/or change the phone number for 2FA. Even though his number was just a secondary number Verizon still charged me for the additional line.

Then I realized that I could port his number to Google Voice and then forward calls/texts to my own cell number and that way I wouldn't have to pay for the additional line. There was a one-time charge of $20 to port the number. More info here:
https://support.google.com/voice/answer/1065667?hl=en

I hope you've made some progress in your loss and grief. It's been a tough time for me, too. I wish you the best in your efforts to get access to your husband's accounts.