Wow collectors are rough....flea market....dont think all of us are not collectors and post stuff with No knoledge....
I also been collecting for more than 30 years, If i had a single hesitation, i would not post the card waiting collectors Time, what would i gain ?
See my other post, you Will find i get the rare stuff all the Time...
I just sold Lord Stanley's autograph and other rare pieces.....
I got this piece in a collection, full of baseball and football, hockey from the 50's on up to late 70's...
The Man owned at least 2000 autographs...in one book called legends...i Must have at least 50 auto's of the best there is, Frank Robinson, Gretsky, Dryden, Gary Carter,Rocket Richard, ....
1969 deckle edge...3 full set and a lot, i mean a lot of 1970 chemtoys.....
At least 4 sets of 1965 tall boys hockey cards...and on and on.....even have a very old Maurice Richard autographe stick, i am guessing this one is from the EARLY 60's...
With all the stuff in the collection and the scarcity of some of the item, i have No doubt..
One more thing, the expert does not own a sport card shop like you said, he is an auctioneer...a BIG one that would not loose is name...too much in stakes for him, i am sure you understand better