If there was a contract for $280 as you claim then why are they discussing different accounts and amounts instead ? It shows that a deal had not been made yet.
I do think that Bob narrowly escaped being in breach of contract.
I think you are just misinterpreting TECSHARE's point here.
If Bob123 didn't wanted to go into the contract with the seller or if the seller didn't wanted to engage in the contract with Bob123, this telegram discussion you are implying would just not exist.
Bob123 had a pri-decided intention to engage in the contract with the account seller and than again broke it intentionally after exposing his digital goods.
There is also a consistent trend of the seller believing the buyer will not follow through with a sale. It shows that the seller knows that there is a risk of a "no sale".
Yes, there was a risk of no sale before the seller revealed his accounts to Bob123, but when Bob123 agreed to buy the account once the ownership is proved the contract should be automatically formed there after IMO.
I find your way of relating this incident to court judgements interesting, but I don't think we could imply complex court laws here anyways there are too many differences.
An acceptance is a final and unqualified expression of assent to the terms of
an offer. Again, there must be an objective manifestation, by the recipient of
the offer, of an intention to be bound by its terms. An offer must be accepted
in accordance with its precise terms if it is to form an agreement. It must
exactly match the offer and ALL terms must be accepted.
Once an offer has been accepted, the parties have an agreement. That is the
basis for a contract, but is not sufficient in itself to create legal obligations.
In common law, a promise is not, as a general rule, binding as a contract
unless it is supported by consideration (or it is made as a deed).
http://www.a4id.org/wp-content/uploads/2016/10/A4ID-english-contract-law-at-a-glance.pdf