How to present work that includes replicating results of another study? I started working on a research project for a class that was at first meant to be a collaboration between a lab at our university and another university. The only information that I was given to start with was a basic problem statement and a vague description of results with no idea of how they were generated.

This work was unpublished and currently they have a paper under review. I tried to get in contact with the authors to get more information, but was unable to. I have been unsuccessful in getting any information at all about the paper that is under review. I was intending to look at extensions of their work or work related to theirs, but with almost no information about methodology and especially context and limitations I was skeptical of their results.

It should be noted if their work is published it will most likely create small subfield. Lacking important information I decided to see if I could, using my own method, replicate these results. I found my own dataset and managed to get preliminary results using the method I developed and from this came up with directions for future work. 

My advisor wants me to present my work at a poster session at an upcoming local event. Is it acceptable to present this work with preliminary results and possible directions for new research?  If so how do I acknowledge the slight contribution from this lab?
I think the best way to approach this is to write a polite email to your collaborators showing enthusiasm for the work and letting them know that you were able to extend it. You may also want to propose if they would like to contribute to the poster. This can strengthen the relations and may result in a fresh collaboration.