Not exactly the same but I'm building a NAS box with old parts. Most of my spare RAM sticks are laptop DDR4 SODIMMs. There are SODIMM -> desktop DIMM adapters... it did not go well. The system would boot 1 out of 5 times. No adjustment of memory speed settings would make the system stable.
That's not surprising. At the speed DDR4 runs, PCB design has to account for all sorts of weird effects. Adding the additional traces on the adapter probably pushes all sorts of timing over acceptable thresholds. There's a reason one of the big textbooks in the area is subtitled "A Handbook of Black Magic". [1]
