Flatten Multicam Clip doesn't work properly on 23.5 Premiere Pro version

When trying to flatten multicam clips on the sequence, it doesn't do it for all of them. Really inconsistent why some work and why some doesn't. Really irresponsible to put an update with such a massive flaw, especially for exporting AAFs with the correct metadata. Works when importing an xml to an older version of Premiere (in this case 26.4 running on Rosetta). Why isn't it a feature to export directly from Premiere to an older version of the same project? Would've been quite useful.