Just chiming in here, I may be completely off here, but my view is slightly different from the other:
It seems crucial to first establish if an agreement was reached with SAS regarding the new ticket. Given that you've made the payment and the ticket has been issued (as per SAS' conditions of carriage, which state that the ticket confirms the contract of carriage), it's reasonable to assume an agreement was formed.
The next consideration involves the authority of the person on the phone to enter into an agreement that would contradict the Eurobonus' terms. I would say that a SAS agent would be deemed to have implied authority (ställningsfullmakt) to represent SAS. Hence, if this holds true, the agreement would likely be valid.
If we accept these premises, it appears SAS has indeed canceled your flight. Consequently, you could be entitled to compensation under EC261/2004 (600 EUR per passenger) and reimbursement for any additional costs incurred.
Taking into account Sweden's emphasis on consumer rights, I think that you should not need to know that the booking potentially was against the initial terms and conditions.