Finish paying with Paypal Express when out of MyCRED points?

So originally we were going to use Paypal Payflow but decided to go with the Express checkout to simplify things. When testing the Payflow the site would automatically let the user complete paying with Paypal if the user was over their credit points. However with Express it only allows either/or. Is there a way to configure it to use both? I’ve looked through settings and couldn’t find anything. Thanks for the help!