If you think a bunch of hairline cracks in the grout and a few cracked tiles is OK, then go ahead and tile over a bouncy floor.
If the current cracked tiles are caused by too much deflection, you need to stiffen the floor. Is there an open ceiling below this floor? You say the joists are trusses. Please describe them with measurements. Do you know the brand? Look for markings. What is the spacing of the trusses? Accurately measure the span. You say you have 3/4" underlayment, did you mean to say subfloor, or do you have two layer of plywood? You're correct about not using CDX.
By the orange netting stuff do you mean Ditra? If so, it's the best thing since sliced bread.
But the floor still has to meet minimum standards. Let us know the answers.