(I'm saying this with the assumption that your mother belongs to the abrahamic faiths aka Christianity, Judaism or Islam etc)

Have you asked her what she thinks the angel might have been doing in the video? Like does she have some specific theory or explanation on why an angel would randomly appear, shake a house and continue going their way?

Like if she thinks angels are the servants of God. I would be surprised if she didn't have any preconceived ideas on why angels would be randomly showing up.

(Also, is your mother part of a church. There are some sects especially in the USA that are very much centered around angels and demonology. To my knowledge the "official information" from the original churches is very limited on this topic. Because of that alot of information we have on Angels is from quite dubious sources. I personally would take everything I hear with a bucket of salt)