getExchangeDetails needs a tradeID to work with rejected offers

[verkhoumov]

I use the getExchangeDetails method to get the rollback_new_assetid parameter, which is available when the trade is canceled. This method requires the tradeID parameter. At the same time, the tradeID parameter of the Offer object is null, since the offer was rejected. Because of this, I will never get a rollback_new_assetid when the trade is canceled.

[DoctorMcKay]

Yes, you've just described reality. There's no way to get trade details without a trade ID.

Nothing gets rolled back if a trade is canceled or declined. Item IDs don't change.