Boy, I don't think so. The yeast are what eats the diacetyl- so once you remove it from the yeast cake, I don't see how it could do the job.
I hope someone else with another idea comes along for you. I'd really like to find out if there is a way to do it.
Of course, you'll be more prepared next time. I always taste the lagers before doing the d-rest (sometimes it's not needed) and always do it when the fermentation is 75% done. Then, I rack and leave it in secondary until finished (or a couple of weeks if it's already done), and then lager at 34 degrees by gradually dropping the temp. I taste it every step of the way, looking for diacetyl. There was a great how to in a book (maybe John Palmer's How to Brew?) on how to see if diacetyl is still present that involves two samples- one to boil, one not and then compare. I'll see if I can dig it up. Of course, that doesn't help now but it's for next time.