Nope.
It will use the default font specified in Preferences > Layout (1) > Default font but as you've noted, there are no additional panel settings for that specific line of information.
Instead you can replicate the same values in one of the information fields that you can set the font and size for.
Something like this:
$Upper(<.ext>) <Sample Rate>, <Bitrate>, <Channels>, <Time>
I've messed about with this a little and have this saved:
$Upper(<.Ext>)" "$If(<Bit Depth>>16,<Bit Depth>" bit, ",)<Sample Rate>", "<Bitrate>$IsNull(<Encoding Quality>,,"( "<Encoding Quality>"), ")<Channels>", "<Time>,)