According to Tidal, yes, HiRes FLAC and MQA will coexist.
Through Volumio, all MQA files will appear as either 48/24, 44.1/24, or even 44.1/16 depending on the file resolution. A 48/24 file will usually be “unfolded” to at least 96/24 by your DAC if it can do full decode, but it all depends on the file itself.
For more info, please take a look at the following thread which also reaches a similar conclusion:
https://community.volumio.com/t/suscription-volumio-and-tidal/