Are “sambar” (electrum) coins minted and used in Waterdeep?

Question

The Sword Coast Adventurer's Guide, p. 13 ("Coin of the Realms") says that the various coins (copper, silver, electrum, gold, and sometimes platinum) are generally referred to by people in the world by the name used by the issuing government. It specifically tries to summarize "Some of the most commonly found, and widely accepted, currency in the Realms". For the city of Waterdeep, it lists the coins as being called nib, shard, sambar, dragon, and sun, where "sambar" is the name of the electrum piece. It also mentions the taol (made of brass) and the harbor moon (platinum inset with electrum) coins, which seem to be separate entirely from the main standard five D&D coins.

In the Waterdeep: Dragon Heist adventure, on page 169, it lists six coins used in Waterdeep. It's essentially the same list as in the Sword Coast Adventurer's Guide (and helpfully has illustrations of the coins) except that it makes no reference to the "sambar" at all. The table of abbreviations on p. 7 lists that "ep = electrum piece", but other than that doesn't seem to actually refer to "ep" or "electrum piece" at all that I can find.

And just to add more confusion, the description of coins in the Player's Handbook describes electrum pieces in this way:

In addition, unusual coins made of other precious metals sometimes appear in treasure hoards. The electrum piece (ep) and the platinum piece (pp) originate from fallen empires and lost kingdoms, and they sometimes arouse suspicion and skepticism when used in transactions.

So, I'm trying to reconcile what looks to me to be conflicting information among these three sources, particularly as it relates to the electrum piece. The Sword Coast Adventurer's Guide seems to call the sambar coins "commonly found" and "widely used", while Waterdeep: Dragon Heist doesn't mention them at all, and the general information in the Player's Handbook (which is somewhat setting-neutral but often mentions the Forgotten Realms) makes them out to be rather rare and unusual.

1. Does Waterdeep still mint these "sambar" coins, or were they only minted long ago (when they were a "fallen empire" or "lost kingdom"?) and are just still referred to as a "sambar" in the rare case that somebody finds one?
2. Are sambars still used in transactions, perhaps raising a couple eyebrows (like using a $2 bill or $1 coin in the United States) but not really being that weird, or would your typical merchant find the idea of electrum coins to be really odd and be unlikely to accept them? For instance, would one ever get an electrum sambar coin as change?

According to a D&D Beyond search (which I believe searches all published official 5E books even when one doesn't have any paid D&D Beyond content), the only reference to "sambar" is in the list I mentioned from the Sword Coast Adventurer's Guide.

Answer 1

Let me start by saying that I have looked at a number of sources that have sections on coinage (Forgotten Realms Adventures [2e], City of Splendors boxed set [2e], Forgotten Realms Campaign Setting [3e], Forgotten Realms Campaign Guide [4e]) and I was surprised to see no mention of electrum coins specific to Waterdeep, unlike many other locations like Cormyr, Sembia, Calimshan, Silverymoon. Most of these sources talk about the electrum inset of Waterdeep's Harbor Moon coins, but that's it. The only exception is the very first Forgotten Realms Campaign Set [1e], which states (Cyclopedia of the Realms, page 10):

Local city states often mint their own copper, silver, and gold pieces, though the electrum and platinum pieces are rarer, usually used only by the more powerful states such as Cormyr, Waterdeep, and Amn mint these types.

So in this case, the adage that the lack of evidence does not mean evidence of absence seems to hold. Hence I looked for secondary sources, in particular the statements of Ed Greenwood, the creator (and longtime contributor) of the FR setting.

As late as December 2017, Greenwood was quoted on Candlekeep.com forums about coins of Waterdeep and sambar was casually mentioned, with no signs of it being removed from circulation or from being minted.

Electrum: sambar (older terms: sandar, serpent)

sambar (tadpole-shaped [oval with a wide three-bend-wiggle serpentine tail] silvery-blue-hued coin stamped with the same markings as a nib)

arms of Waterdeep face (the “front”) is “the blazon” and the stylized Mount Waterdeep face is “the mountains”

I realize that Greenwood's statements are not official, but they carry enormous weight and are considered canon by various long-running FR communities (like candlekeep.com, FR wikia) unless they are contradicted with printed material. (I am posting this answer after being encouraged to do so in a comment by @V2Blast.)