Just as titled, received a friendly request then decided to quit my alliance, and immediately received flashes of alliance suggestions, but chose to search for the specific name, got it and also as shown.
Went back to the search list, clicked on two more random alliances, one had its join button green ready to be joined and the other grey out like the one in pic.
If you are looking for a new home we have room in The Locker. As long as you are not intimidated by 10/11* titans and war opponents with 4K+ defenses, we would love to have you join us.
I appreciate the offer, was just going for a brief visit anyway, but apparently the requester set an impassable filter, I have since then returned back to base.