I think the likelihood of the team moving to Las Vegas or anywhere else is low. Probably very low. But not zero. Lots of teams move, lots of teams who appear very likely to move, don't (I'm old enough to remember when the Sacramento Kings moving to Virginia Beach was viewed as "very likely"). The future is hard to predict sometimes.
I wish Mr. Angelos good health of course, but no one lives forever, and as others have stated it's not a given that the sons will own the team, whether that's due to MLB interference, tax issues, or just disinterest in doing so. The MASN case, the continued competition with the Nationals for the hearts and minds of area fans, and dwindling attendance are all issues to keep in mind down the road. Even if they don't result in the team moving, they could still impact the team's ability to compete.
I don't see anything wrong with 105.7 having a lawyer appear on a talk show saying he heard of or knows of an offer to move the team to Vegas. Maybe someone did offer to buy the team but Angelos turned it down. Who knows.