Dealing with this all as a hypothetical and not injecting any experienced LEGAL opinion. (I am not an attorney and don't pretend to be). Just for the sake of debate and such,

This scenario starts off a little different than the first one.

First, A didn't seem to represent the chip as anything. There might be info missing. Ie., when A sold to B, what sales pitches were made. Did he/she suggest the possiblity of repairing the chip and filling the cancellation....?

Here you have a possible liability of the repair person, (Party C) in that he/she is repairing a defect that was intentionally put there as a control to prevent fraud. If as the last part of the post said, Prty C, does this frequently and has done many, he/she should know that the cancellation is an intentional control and that repairing it might lead to an incorrect or fraudulant representation of the authenticity of the chip. Unlike the issue with the seemstress who was repairing a piece of merchandise that was unintentionally defective. To repair a blouse that is torn and missing buttons would not be the same as removing the markings from a canceled deck of cards or a cancelled or drilled chip.

The later could be a participation in a fraud if that repaired chip later gets represented in a wrongful or fraudulant way.

You should have another party here but I will put it B-1 and B-2. B-1 should have left alone and not altered the cancellation. While she didn't committ fraud, her actions lead to the possiblity for a later fraud. Thus some liability. B-2 might be able to be considered ignorant. While probably still liable would be able to hold Party C and the estate of B-1 responsible as they engaged in an act that led for the innacurate valuation of the chip.

Party D. might have some liability also. Auction houses should have a responsibility to seek out a proper and professional appraisal of property before they value and list them. They could, possibly, hold their appraiser responsible for their damaages.

Party E, might be able to escape some responsibility. If I were Party E, I would, If legally possible, try and join Party H in the suit against others. Both of these buyers bought based on other representations that should have the confidence to be correct. If party E has any liability, it would be that he/she didn't independantly authenticate the chip before relisting it. Buyer beware. If you buy something on one of the Auction Websites, recognize the possibility that you aren't getting what you think. Before retrading an item. Cover your butt and get an independant valuation and authentication. You would probably be held responsible.

Party F, is a reference book and didn't represent the specific chip as anything. Unless information in that book is incorrect and could be judged to have led to a misvaluation or misidentification of the chip. I, as a layman, of course, wouldn't see a liability. Party G, the second auction service, should have similar liability as party D. While not as in control as D, as they didn't have possession of the merchandise and thus no control of it's listing.... The auction lister (Party E) has that responsibility but the auction website might be seen as having some liability for policing such situations. Some info might be needed here. Were they notified by other collectors that this auction was fraudulant or based on missunderstandings of the authenticity. Were there complaints about the seller in the past.... Did the auction website do any reasonable action to follow up on concerns or complaints.... In any case, if held responsible, Party G might come back at E also, even if he/she was innocently incorrect with their representations. Thus sparking another lawsuit on the matter. Party E against other previous parties.

some possible match ups,

H v. A-E
G v. E
E v. A-D
D v. their appraiser
B2 v. B-1(estate) and C.
...