Hi, Joe. About any stripper will remove poly and no stripper will remove stain totally. A stripper might take a little of the stain off but it is not made to do that.
The choice of a stripper is yours. Many strippers are methyl chloride based. I have some safety issues with these but no stripper can be totally safe. I am a little more comfortable with an NMP based stripper like Citristrip. It does take a little longer to work. There is a lot of info on the web about strippers and the chemicals in them so you should do your homework on this and get what you feel comfortable with. Whatever you choose, be sure that you follow all the safety warnings. Having good ventilation in the work area is critical as is keeping kids, pets and unknowing others away. Be sure you wear chemical resistant rubber (not latex) gloves and eye protection.
I would be interested to know if the poly you used was oil based or water based and how long it had been on. I usually use oil based which is naturally amber/yellow and know that water based does turn over time. If you could give us some idea how long it took for yours to turn and anything unusual about your service conditions, like if it was in constant sun or right in front of a heat and air conditioning vent, for instance, this might help others. Some people have noted that their wood or stain picked up some yellow color from Citristrip, but I have never noticed that.