I don't think a mention of a stock on HC pulls in $222k worth of cash at the end of a trading day tbh.
Seems like RDN taking the full 2 trading days to release news. It's unlikely to be cap raise as they have $1.38m cash and spent $360k quarterly.
Looks more like a standard leaky boat with late arvo volume pumps the day before news, like GPP before it launched. Alternatively, could be nothing and the company releases a standard "no, no, no" announcement.