Oh, and yea, you can just log "requested lambda" and injection time. Your AFR should generally follow the lambda request unless you max IDC (calculated as "inj time" * "rpm" / 1200). That part is only true for "moderately" altered software, though.
EDIT: weird, the "specified lambda" is supposed to show in gr. 31, but your log has zeros there. I don't use VCDS myself, so can't say whether that's normal or not.