The husband will still be a bit distrustful if he's asked about making copies. In this case he will ask Emet and his crew how he can trust them and won't just take the items and schematics to sell his late husband's work. We'll leave it up to you how Emet will convinced him of his trust and worthiness.

The relics and schematics themselves will note improve engine speed for ships fitted with the proper magitech. Since this technology is still new it might be hard to understand. But the relic items included are pieces of old world engines that might be able to be refurbished.