In reality, FIDE Dutch was only “faux” deterministic. It’s deterministic if you can pair the section successfully following the direct rules (which calls for backtracking at most score group to fix major problems). If you get to the end and can’t pair the last score group and can’t fix it by unwinding to the previous one, then the current rules have a (very) convoluted process for backtracking through even higher score groups which eventually results in a whatever works. The 2025 rules simply punts the whole question to
1.9.3 If it is impossible to complete a round-pairing, the arbiter shall decide what to do.