Well actually, RCB is struggling because their owner Dr. Vijay Mallya is in a financial mess with his Kingfisher and UB Group. His net worth has dropped considerably last one year and hence is affecting his IPL franchise and F1 team, Force India. He is in a turmoil but is desperate to hang on to his posession and has been making headlines in India esp Bangalore.
DC, have been underperforming for a while now. And that may be one of the key factors for not generating enough revenues and profits.
Apart from that, I believe all the IPL are following the deadlines and paid off the players unlike the BPL franchises.