The non-original paint is completely irrelevant

If you knew how many deuces, (not to mention non-supercars) were repainted because the owners felt like it - you would be shocked. My deuce was repainted in '71 or '72 - does that make it a conspiracy? 'Cmon, you are fishin.
(BTW, the story we (Brian & I) got regarding the repaint, was that it was repainted the color of Earl's niece's eyes. If that ain't sweet, I don't know what is. I think that story was news to Earl when we told him, but.... I thought it added some personal history to the car.)
As far as value.... who knows. Of course the $100k+ offers were very high - higher than any restored car has ever brought, much less a project car. But remember, the deuce world is different in several respects. (Don't flame me, this is an educated opinion - educated from knowing what every deuce has sold for in the past 10 years

)
First, the deuce novas do not sell nearly as frequently as the y-camaros, or y-chevelles for that matter. So, when a deuce 'is' sold, it is not unusual to see large price disparities between sales events - whether it's a project or a restored car.
Second, the deuce novas do not have a non-yenko copo 'following' like the camaros and the chevelles to 'track' the values; ie; each time a yenko camaro is sold, everyone does a wallet check, and when a non-yenko copo camaro is sold for the same value or more than the last yenko camaro - the yenko camaro owners perform another unrealized gain calculation. The deuce novas don't have another 200+ non-yenko copo fleet in circulation to guage selling prices from, so each sale is a stand alone event without anything else to show progression.
Third, the market has changed. 4-5 years ago the primary deuce buyer was a guy who wanted a deuce, or two, or three. Today, the market includes an increasing subset of buyers who are completing collections, and have decided to include a deuce. This subset is capable & willing to pay more than the buyers of 1 year, 3 years & especially 5+ years ago.
FWIW & IMHO, the current deuce value for a car restored to high standards, with original drivetrain, and excellent paperwork is $150k. I think the offers made on this car were unreprecedentd & extremely good for the sellers, and the offers were within reason for the potential buyers to get the car restored - hold it and enjoy it for a few years - and still not get upside down in the event it needs to be moved. So, if the sellers were 'testing the waters', I believe they found the sweet spot faster than they thought. However, as we all know, this could all change tomorrow