IF Statement for two columns

I am trying to enter a value in a cell based on the results in 2 different cells. if cell 1 is blank then refer to cell 2, based on what's in cell 2 return X value.

If cell 1 is NOT blank, based on what's in cell 1 return X value.

here is what I have so far, so far everything that looks in cell 1 returns a FALSE.

=IF(ISBLANK(E8),IF(D8="401K Employer Match","Match",IF(D8="401K Percentage","4K",IF(D8="ROTH 401K %","4R",IF(D8="Life Employee","LIE",IF(D8="Life Spouse","LIS",IF(D8="Life Child(ren)","LIC",IF(D8="Life Employer","LE",IF(D8="Life Employer X 2","LE2",IF(D8="Short Term Disabilty Base Pay","STDB",IF(D8="Short Term Disability Gross Wages","STDG",IF(D8="Short Term Disability Over 60K","STDB",IF(D8="Long Term Disability Base Salary","LTDB",IF(D8="Long Term Disability Gross Wages","LTDG",IF(D8="Long Term Disability Over 60K","D")))))))))))))),If(E8="Reliance Dental","DE"))