Faking a death: procedural believability

I'm writing a story set in a small town in Maine. It's a slow-burn mystery focused on the puzzle, rather than a high-octane action thriller, so while the reader is obviously expected to suspend their disbelief to some degree, I don't think it can get away with being as ridiculous as an action-packed thrill ride.

The story involves two characters faking the death of their brother in 2013. He was already terminally ill, so I'm assuming that means less scrutiny around the death. There are two main elements of the deception that I need to fine-tune so that they're at least in the general ballpark of reality:

1. The death pronouncement and certificate. One of the two siblings is a doctor. If he claims he's familiar with his brother's condition and checked him after death (he "passed away" at home), can he sign the death certificate? I take it this would be necessary to obtain a transport permit for the body from the town clerk. I can't have a hospice nurse or other doctor examine the "body" because even with an expected hospice death, there's no way their examination would be so cursory that they could miss the guy still being alive. So, the question is whether the doctor brother can pronounce him dead, sign the certificate and all that, without any other medical professional independently verifying the death. (I take it a doctor certifying the death of a family member is not illegal, though it's problematic from an ethical standpoint and could've gotten the character in trouble with the Maine Board of Licensure.)

2. The burial arrangements. Apparently, Maine law allows for the "authorized person" - which would be the siblings in this case, because the man whose death is being faked doesn't have a spouse, children, or living parents - to handle the burial themselves. The way my story is written, there's some minimal involvement from a local funeral home, but it's mostly providing the coffin and helping with paperwork. Once they received a duly signed death certificate, they were satisfied and didn't have any reason to suspect foul play. The siblings simply put something else, that weighs roughly the same as a corpse their brother's size, inside the coffin they bought and carried/had it carried to the garden beside their family home, where it was buried in a private burial plot. The idea is that no one actually saw the supposedly deceased - not the funeral home employees (since they didn't actually "prepare" the body for the service or place it inside the coffin or anything), and not the funeral attendees, since the service was closed-casket.

So, I'm trying to figure out if this scenario has enough basis in real-life law and burial procedures for the 2013 Maine setting that readers would probably be willing to accept it, or if it's too far-fetched to work even in a work of fiction. Thanks in advance, I appreciate all input.