As noted, Rhyno returned to Impact at the recent Slammiversary 17 pay-per-view in Texas, appearing under a mask for an attack to Michael Elgin. Rhyno was never un-masked, but it was clear that this was the master of the Gore.
Rhyno was technically still under contract to WWE when he appeared for Impact. Regarding any potential legal action, Pro Wrestling Sheet reports that sources say WWE likely will not be taking any action.
For what it's worth, Rhyno is still listed on WWE's active RAW roster as of this writing.
As seen below, Rhyno is among those featured for the three upcoming events that Impact is partnering with Championship Wrestling From Hollywood on - Unbreakable on Friday, August 2 in Santa Ana, California; Star Struck on Saturday, August 3 in Hollywood and airing on Twitch; Impact TV tapings on Sunday, August 4 in Port Hueneme. Tickets are on sale now for all three events.