I brewed the grapefruit pulpin all grain, and I only put it in the secondary for about 10 days. Tossed the vodka soaked peels into the keg on the 10th day along with the brew.
As I recall the grapefruit flavor stayed strong through the whole keg, and it was not consumed all that quickly (it was a bit over 7% abv ) I also dry hopped 5 days into the secondary.
I bet it will be good. I have dry hopped New England IPA’s in the primary like 2-3 days into fermentation, then other batches in the keg only .... they all turned out great. So who knows, you may have brewed the best tasting beer you have ever had, I am constantly amazed at the amount of variability that can be introduced with either no detectable difference or at least not harming the taste.