so rack and mudguards fit in one eyelet should be fine.or am i missing something.
For lighter touring with reasonable loads, you should be fine hanging both rack and mudguards from the same eyelet.
Where it becomes important is touring with larger, heavier loads. The longer bolts required to hold both stays and rack can lead to shearing under expedition loads. This (and convenience) is why touring bikes intended for heavier loads have double eyelets. It is also why expedition bikes like the Nomad have 6mm fasteners -- that extra bit of design to ensure reliability.
For the kind of touring you intend, I see no problem with just a single set of eyelets if that is all the frame has.
If your Tubus rack is not an Evo model, it may include a mounting point for the fender stays as well. This will provide a second mount, as would a Thorn rack (as Chris observed).
Best,
Dan.
