I also had this problem. On Apr 5th about 5:30pm I completed the feat. When I went to look for the portrait and feat rewards it was not unlocked.
I waited for swgoh.gg to log the GAC results and took a screen snap of the battle results showing I'd completed the battle and when.
I went to EA help and tried to report this. After a week of wrangling with them, trying to get the information they were requesting and so on, I finally got a service rep to call me. They consulted with their experts there and came to the conclusion that they had no way to verify the feat was earned, even with the swgoh.gg picture, and had no way to compensate me for the feat achieved without their verification.
Their only advise was to come here and make a technical issue post. In doing that, I found this thread already started, so decided to tack my instance onto it.
If it helps, I have multiple EA service tickets referencing this.
80531880 (original)
80136756
80531880.
80599940
80599233
The others were because EA kept asking me to open tickets using the in-game help feature, which took me back to the website and and opened a new ticket. Really poor instructions for doing wat they asked.
Thanks