Thanks again nc50lc. I raised an issue https://github.com/spesmilo/electrum/issues/7893. The responses have been very interesting although somewhat disheartening. They're saying that prior to version 2.0 Electrum used a fixed word list; and if my word list is not in that list it could not have been generated by Electrum; so basically I must have used a different wallet to Electrum.

Well, I know the date of purchase 100% during 2011 or before 2011.
I know 100% I used a wallet that generated the 12 word seed which I wrote down and found in my note books.
I know 100% when I plug those seeds into Electrum they're accepted by Electrum without issue; but wallets display zero balance.
I know 100% I successfully transferred coins between the wallets over a very short period of a week or 2 max and then never touched the wallet or Bitcoin again until 2016 or so. By then my PC were long broken and got rid off.

I'm now trying to understand whether my 12 word seed was generated by a post 2.0 version of Electrum or some other wallet type.
Does anyone have an idea what wallet type that had the same look and feel as Electrum existed in or before 2011?
There has to be an answer to this mystery. Let's solve it.