A little worried about substitution

[Burnt Toast]

The thing I'm worried about is that the fake urine is yellow but it has no odor. Should this be a concern?

Nope. Because a lack of odor can be had in human urine samples as well as synthetic.

Its the samples with the odd, unusual odors that raises red flags with the UA techs. Like odors that are not supposed to be present in human urine (i.e. bleach, household chemicals, etc).