New photos and video, obtained by TMZ, show Benny sipping on a drink and making a few bets at the Wynn Thursday -- right around the time Justin and Hailey Bieber announced they were expecting their first child together.

The reason that's relevant ... well, Selena posted some snaps of the two of them around that exact same time as well -- kinda making it seem she was with Benny during the bombshell.

Take a look ... there's BB at the table, doing his thing and minding his biz. Other photos we got a hold of show him walking with an older woman -- who looks to be his mother.

We're told this Benny sighting happened around the afternoon -- and that he was in the building from 3:30 PM to around 8 PM ... with no Selena in sight.

Again, it's NBD obviously ... but what it suggests is that Selena might've intentionally posted those lovey-dovey photos of herself and Benny on the heels of the Bieber announcement.

As we reported ... Selena Gomez posted cute couple pics -- including a black and white photo of her and Benny holding hands -- just a couple hours after Justin and Hailey Bieber announced their pregnancy news. It was hard to decipher at the time if those went up by coincidence ... or if it was meant to send a message to her ex, Justin, and foe, Hailey.

Some took Selena's post as her response to the news ... flaunting how well she's doing in her new relationship, highlighting the fact she's moved on. But, if Benny's in Vegas ... it's unlikely those pics were taken yesterday ... they might just be old shots on the camera roll.

That said, we don't know for sure Selena wasn't in LV too, keeping a low profile. We don't have any evidence that she was though ... and word is, she's been filming in NYC.

JB and SG's relationship timeline's pretty well known ... months after they broke up for the final time, Justin went to a New York courthouse to marry Hailey -- and the two have lived in bliss ever since. Of course, Selena and Hailey have been ensnared in conflict on and off.