I recommend opening a case with JTAC if you can. I'm losing my test environment shortly so I'm not going to be in a position to replicate the behavior for JTAC.
From poking around it looks like this behavior has been around in some form since 10.0 (see https://lists.gt.net/nsp/juniper/20925). Since it works properly on the QFX5100, but not EX2200/3300/8200, I'm not sure if this is a platform limitation, and the KB mentioned in that post shows "Article is in review and not available for viewing". I'm not certain, but I think I've tried to pull up that KB article a few times over the past year or two and got that error every time.
Cheers!
-Chad