Assuming a fairly standard OG of, say, 1.040 to 1.045 I think the beer will be undrinkable with 7.8 IBUs. There will not be enough bitterness to balance the residual sweetness of the malt and make it pleasant drinking, IMO, particularly if it was all malt extract.
You will need to get the IBUs into the 20s at least if it's a regular pale ale, lager, etc, and aim for the high end of this range probably. BeerSmith will tell you the IBUs for the style.
I would definitely do a mini boil with some hops, cool it and add it to the fermenter, strained. Use BeerSmith to work out your volumes and IBUs. I am not sure if you can use BeerSmith to do the calculations about what the mini boil will do to the IBUs of the total brew, so you may need to do some manual calculations. Unless someone can tell me that it can be done in BeerSmith??
What was the recipe? Tell your mate to download the
BrewMate recipe designer, which is free, so he can avoid such a situation in future.
Oliver