It sounds like one of those times when it is REALLY hard to tell... Limelight is pretty cold hardy and it may just be having difficulty coming back and creating another set of buds (if the stems are alive) or developing a new set of stems. If the last cold snap was 2 months ago, that would concern me as I would have expected to see something indicating it is working on replacing the stem buds or the stems themselves.

I would take one of the stems and prune it in 1 or 2" increments until you hit green or hit the bottom. If the stem is all dried out, check others in a similar manner. If all of them are dry, there may still be hope but just a little. The roots may be ok and it is more difficult to tell how are they doing now becvause you just have to wait and see. At this point, you need to decide what to do next.

I would give it TLC and wait another growing season. Maybe provide some special winter protection if it has not leafed out this year at all. Maintain the soil moist (not wet) and keep it well mulched with no fertilizers (some weak fertilizers like liquid seaweed would be ok this month only). Maybe a little (1/2 strength) of muriate of potash (pottasium) and some bone meal (phosphorus) at half strength this month and next. Phosphorus is for roots and pottasium for overall plant health.

Thank you for these excellent suggestions. I tried snipping back the stems and the result was not good. I found no green so unless there's some life left in the roots she's a goner. Other shrubs appear to have suffered the same fate. There's no evidence of disease so I guess just one of those fateful springs where the weather gods were extremely unkind. But I will wait until next year before hauling it out of the ground and meanwhile will give it the attention you advise. Thanks again.