Well, it's not beyond belief that a person wouldn't want to have their 80th birthday bash in the middle of covid. Maybe they feel better about the situation and decided to have it now. Why not in July, you ask? Well, with so many baseball people involved in it, it's also reasonable to think that they would wait until after the World Series. Didn't that just end?
No MLB manager would say those things in the media. How they talk in person off the record, I have no idea.
Apparently, TLR and Sammy Hagar have some history:
https://fullinbloom.com/sammy-hagar-tony-la-russa-showing-me-how-to-throw-a-baseball-properly-flashback-friday-2007/
https://patch.com/california/walnutcreek/calendar/event/20210311/995064/tony-la-russa-s-arf-stars-to-rescue-virtual-2021-walnut-creek
"Tony La Russa’s Animal Rescue Foundation (ARF) once again brings a dynamic mix of talent with the 30th annual Stars to the Rescue, this time in an all-new virtual format.
"This year’s star-studded show features musicians and comedians from the past 29 years of Stars to the Rescue for a special reunion special, including Gloria Estefan, Luke Combs, Trace Adkins, Sammy Hagar & The Circle, Bruce Hornsby, The Doobie Brothers, and more! "
Maybe the guy offered to buy him a beer and didn't realize that SW wasn't serving beer. Or, maybe he offered to buy him a beer after they got off the plane. Or maybe he's just one of those people who seem to reflexively offer to buy people beer to be friendly.
But once again we will defer to your omniscience and ability to definitively make claims after being presented with only shreds of evidence.