It refers to an organized donation collection, like might happen at a church (pass the plate/bucket, or drop money in the box at the back). Or at a museum (a money collection box near the entrance, usually with a theme like a coin rolling race or an animal that eats the money, etc. In this case, the donation was advertised as being for this girl (reason is unlisted) is being organized at a bank, presumably there is an account set up with her name attached/labeled for whatever the situation is.
The people organizing the donation are not currently asking for money, but perhaps they were in the past and expect to again in the future; for instance, if she was recently hospitalized but is now home (and may be in the hospital again later).
edit: I just saw the word "reward" in relations to this fund, "reward" in this context relates to someone who is a victim of a crime -- she may be missing for any reason, the victim of a crime, or both; if the case is solved the money collected would go to the person/people who contributed the missing piece of information that allowed the case to be resolved and/or the money could be used to help cover costs of solving the case or addressing some issue (eg. if she is found, but there are medical costs due to injury, the money in the bank could help cover hospital costs).
Doing this through a bank allows for balances to be printed along with a record of who donated and who withdrew the money, and when. It adds a level of confidence for the people who are making the donations that the money isn't just going to some random person's vacation (or that the person can be sued if it is used for pleasure, because there would be a record of the withdrawl).
edit 2: it may be related to this, it appears there is a bank account the family has set aside, it currently has $14,000 USD toward information that will help close the case (she is listed as missing at present), the very end of the article mentions the info you may be asking about regarding donations: [Community marks ten years since teen's disappearance](https://www.lex18.com/news/covering-kentucky/community-marks-ten-years-since-brookelyn-farthings-disappearance)
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i've heard 'take up a collection \[ie of money\]' for some good cause. this is probably just a variation on that.