Finding friends for elderly mom?

My sibling recently moved our 90 yo mother to another state and set her up in a condo to live by herself (if you think this sounds insane, I completely agree with you). I just went to visit her and it's clear she's completely isolated and lonely. She isn't interested in senior day centers but would love to meet a few people that she could enjoy one on one. The condo community is large but looks to be mostly young people. Any advice about how I can help her make some friends? She's not very mobile and I get the sense that my sister only visits her an hour or so a week. (Moving her closer to me isn't an option because my sister has control of my mother's finances. )