Apple ID of deceased member of family deleted but devices are still locked

For information about how to request access to a deceased family member's Apple account data, and possibly their equipment, read this support article --> How to request access to a deceased family member’s Apple Account - Apple Support

Did you follow the procedure as outlined in the above article? I only know what it says but it implies that you can get access to the account and using that you can remove any lock on the devices. Refer to How to remove Activation Lock - Apple Support There are only two ways to remove a lock:

#1 If you have the necessary information you or the signed in owner can do this yourself by simply signing in with the owner account and password information. If you use this method and this is a new device to you, follow unlocking by doing as outlined in What to do before you sell, give away, or trade in your iPhone or iPad - Apple Support or What to do before you sell, give away, trade in, or recycle your Mac - Apple Support

I have never needed the service but my understanding from the support article is that they give you access to the account that was used to set up the service and you remove the lock yourself using that account. Since you requested the account be deleted, to use this method the account would have to be re-instated. If Apple sent you a long code, contact them again with that code. I don't know if this works in the case of a deceased user account though; that's simply what Apple says in How to delete your Apple Account - Apple Support

Making a request for the removal of an activation lock is a completely different method and has nothing to do with a deceased person's account. Apple has a very strict protocol for handling these requests and what they will accept as information. You will need to contact Apple itself about the issue with their not accepting a receipt from an authorized dealer. Refer to this page for Apple Support features ➔ Contact - Official Apple Support

Select from the presented options until you find a solution for your issue, or see if there is a chat or phone call contact method offered lower on the page under “Get more help” (you sometimes have to narrow down the options multiple times before this is shown). If you do not see your issue, keep experimenting with any series of selections until you reach one that offers a chat session or a telephone call and get the representative to redirect you.

This support article has various country telephone numbers for contacting Apple for support and service ➔ Contact Apple Support - Apple Support For some countries look under “Other” listing at the end of the list. Not every country has telephone support, and phone numbers may only work when calling from the same country.

Remember that this is a user-to-user support forum. We can't do anything to actually resolve this for you other than provide advice. If you contact Apple you may need to be persistent about the lock request. I get the impression from the way their system is setup and the web page structure that it is a completely different group of people from regular support.

This is a worldwide visible forum and Apple will remove personal information from posts to prevent you from ending up on a spam list. Likely your image had an address or telephone number on it.