Eren's preemptive attack had caused a great deal of damage to the flesh golem.
It had lost its skin. And the Blitz Shards had destroyed the corpse's muscle fibers that had gotten exposed because of no epidermis as well.
The flesh golem transformation, however, seems to have allowed the creatures to heal some of the wounds and injuries they suffered beforehand. The flesh golem Eren was confronted with also managed to recover some of its strength by regenerating the flesh that was destroyed by his spell.
Of course, Eren's attack wasn't completely useless. The flesh golem didn't seem that threatening to him when compared to other flesh golems his team members were currently facing. It was as if recovering the charred muscles had made the flesh golem transformation less threatening.
