How about a consolidation loan? Or a CC from a credit union.
Getting approved for another line of credit with high utilization usually gets approved based on consolidation or high income, with an ability to pay back loan.
$450 a month is a high payment, one would try avalanche or snowball method. After 6 month to a year and only 1 card having a high utilization go for another card to balance transfer.
JMO, hope the experts chime in with more info