Where someone is going to part with £100,000 I fail to see what difference £250 will make, to say it's a drop in the ocean is an understatement. If taking the moral high ground is priority, then you shouldn't even consider applying to a course that asks for so much cash, because even if the assessment was free ... you are still being ripped off by the overpriced training if successful at said assessment day.
And for the chance to have the full training and TR paid for, i think not even applying to it because of a small assessment fee is a bit unappreciative of what the company are actually offering.