Welcome on forum 3dwannab,
On 'Defpoints' are only these small dots, which are placed from where to where you measure and place your dimension, nothing else. 'Defpoints' layer is not-printable (that's why there is no this layer in PDF), so the mentioned ticks wouldn't print either and you wouldn't have problem with PDF.
You must do something wrong or unusual...
I don't understand why do you have to freeze 'Layer 0' to turn off dimensions. It seems like you use custom ticks saved as a block on wrong layer... However you said when exploded it's 'Layer 0', which should be OK for creation blocks, because the ticks should take properties from the layer on which they and dimensions are placed.
Check properties (layers) of the block you use for ticks using INSERT command, without exploding it, maybe this will throw light on your problem.