I have found a solution to the problem and in the context of the way I am using the equipment. I am using the Profire 2626 to playback sounds through 8 independent speakers.
To access the input/output channels indpendently, you have to read the audio interface as an ASIO interface driver. The function 'audiodevinfo' reads the interface as a 'Direct Sound' driver, as a mutlichannel device, and does not allow access to different line channels e.g. Line1/2. Only matlab versions 2013-2019 (from what I can tell) have the package necessary to interact with ASIO drivers (that I can find..), I used matlab 2015b.
As a precaution, I edited matlab preferences such that it only reads sound driver cards as ASIO drivers. Then it's just a matter of getting acquainted with the 'dsp.AudioPlayer' function which allows you to create an object variable to interact with the audio interface, i.e. p = dsp.AudioPlayer. Then, changing p.ChannelMappingSource to 'Property' enables custom channel mapping through p.ChannelMapping, e.g. p.ChannelMapping = [1 2] will allow access to lines 1 and 2. In my set-up, I actually use separate instances of Matlab to access the different channels (for different reasons), so the mapping part is trivial; at least when I tried, using one instance only allows you to have only one dsp.AudioPlayer object and therefore you may not access the channels independently.
Also, depending on your file type, features related to the file, and employment requirements, you might have to change other parameters in the object. If not, you will experience data loss or system efficiency, resulting in unwanted effects to your data files as they are recorded and or played back.