Failure as in performing under Toei/Bandai's sales expectations or failing to match the sales performance of the Kyoryu merchandise. Not everything has to do with episode counts or ratings.
And the suits and monsters aren't the problem. You can always write around it. The story scenario writer and the head producer are. The latter one in particular has produced two of the most disappointing shows in recent memory. The same for the scenario writer. If this show fails, it'll be a good chance we won't have to see her writing for Toei for a long while.