Friend Scammed of Life Savings by Cashier Check. Is there any hope?

tl;dr what kind of investigator or other person could help us track down money withdrawn from Friend's savings account by cashier check. Friend did so "voluntarily" but we now know (1) she was acting under undue influence of a scammer and (2) is not remembering events that she should remember and therefore (3) she is not currently competent to handle her own finances.

We have a friend who, we now realize, is no longer competent to manage her finances herself. Friend's husband died a couple years ago and Friend has two children who are both over 40. Daughter is trustworthy. Son is not trustworthy. Son is a liar on other issues. Son has abused privilege of using Friend's credit card. Son is likely complicit in this scam but we do not know that and he denies it.

At some point Daughter becomes aware that Friend has 0 balance in savings account. Friend doesn't know where the money went (and she's not lying, she has forgotten). Daughter eventually talks to bank tellers who tell her than one day Friend came in with a strange man (not Son, who tellers would recognize) and withdrew the entire balance with a cashier's check (as I write this I realize I don't know whose name was on the check, Friend or Scammer). Daughter pieces together that Scammer claimed to be a money manager and "befriended" Friend. Apparently they were socializing together (non-romantically, but Scammer and gf invited her out to dinner etc). I assume he won her trust over and then told her how stupid it was to be earning 0.1% in a savings account yada yada yada now she has zero balance and Scammer isn't picking up the phone.

This is purely my speculation, but I am assuming the funds have already been converted into cash gold or bitcoin, and I am assuming this guy is in another state now. This was nearly half a million dollars. Is the money gone, like gone gone? Any chance of rewinding any part of this?

We are addressing the problem of future management of finances, but that's a different issue. Is there any way to get any of this money back? We've been unable to locate the guy but have barely started. We know we need an investigator but what kind? Forensic accounting? Bank fraud? Are those the same thing?

My basic concern is that this is not even a "good" financial scam with fake LLC's and fake documents etc. so I'm skeptical there will be much of a papertrail. I guess at the very least, he deposited or cashed the cashier's check somewhere. I don't think we even know that yet.