Naturally, you can do that here also. You are, after all, looking to mitigate the loss experienced by the breach of your setup, and taking the iron fly off for 25% of max would accomplish that task. Naturally, if taking off the rolled fly for 25% max profit would get you back to scratch, then I would definitely do that here.
If taking the whole fly off at 25% max isn't going to at least get me back to scratch right away, rolling to the fly can still provide me an opportunity to mitigate loss, since at expiration at least one side of the fly is destined to expire worthless (price can't be in two places at the same time, after all). Naturally, this means that I will have to roll one side of the fly again, hopefully at a point when price is such that getting a credit is more feasible.