I am working on adult mortality in Burkina Faso, however I have problems finding some variables. Looking at the forms, I noticed that in censues of 1996 and 2006 questions where asked about the number of deceased, their age at death and sex during the last year preceding the survey. However, I cannot find these variables in datasets.
You are correct that questions were asked about deceased members of the household in each year of the Burkina Faso census. For 1996, you can find the mortality data here. You will need to download the relevant file and merge it to your IPUMS extract. Unfortunately, the 2006 mortality data is not currently available for Burkina Faso. I would suggest directly contacting the National Statistics and Demography Institute in Burkina Faso to see if they are able to provide you with the 2006 mortality data.