Not necessarily true, at all.
If you pal park it to D/P, they should all be 00, if you pal park it to platinum, the only one that shouldn't be 00 is the 46h value which should say 37. If you pal park it to HGSS, then it should say 37 in 46h, and the only other one with an entry should be the 85h value which will correspond to the pokeball it's in (eg 04 if its a pokeball).