I'm not looking at the recipe at the moment, but I assume you're referring to KO or whirlpool hops? Dry hops won't have the exact same effect, but I wouldn't call the subtle difference bad either.
Lee
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Perhaps you could make a small amount of wort at the matching gravity, then throw them in when you cut the flame. Just an idea. Shit, it might even work! Let us know what you end up doing.
The dry hop plan will work nicely, but it won't contribute the exact same flavor. I whirlpool for about 15 minutes after flameout (basically while I set up the plate chiller), so I get some utilization from that. Having said that, in that beer, the hops blend so nicely that you won't mind. Drink it all and brew it again!