Could scan_tx be used for importing a specific deposit TXID for a 2-of-3 multisig transaction?

[starlingfarchecker]

Could scan_tx be used for importing a specific deposit TXID for a 2-of-3 multisig transaction in order to avoid syncing weeks of blocks between the multisig creation and multisig payout (cases where the traders need to wait for shipping or job completion)? scan_tx initially worked to import the deposit TXID but it was gone after import_multisig_info, which could be related to detach_blockchain or refresh.

[rottenwheel]

Another thing is that subtractFeeFrom didn't seem to work when trying to spend the entire wallet balance in one TX, i.e. send the payment to the seller and send the fee to the mediator in the same TX (with the TX fee deducted from the mediator's fee). It reports either tx_not_possible (insufficient funds) or leaves dust in the wallet. Due to the multisig UX, it is much easier to have a single payout transaction (instead of needing to do another transaction and go through the sync/export/import/generate/sign/broadcast process again to pay the mediator's fee, after the other trader has probably already left).

A solution would be to fetch the proposed fee via a non-broadcasted dummy TX, then statically set the real TX's fee to this proposed fee, but it is not possible to statically set the fee with monero-javascript. And if I make a new TX with the proposed fee deducted from the mediator fee, the dynamic fee rate changes which results in either tx_not_possible or leftover dust.