Vauge at best, (Kinda look like Karoot ?) The only 40k army close to Lizardmen is the old discontinued Space Slann from back in the rougue trader days.
Lizardmen was genetically engineered from wildlife on the particular planet WHFB takes place, and the Tau is a young race that evolved long after the Old ones no longer existed. So no not the least...even though kroots look familiar in some ways they too evolved on their own (to my knowledge)