So €500 for an assessment? For a seasonal airline that is a very clever way of getting revenue in the lean winter months.
Also, if this company were to downsize or vanish, you're out of a job with a worthless rating. Yes the MEB3 may count the hours toward their requirements but if you are out of a job you're not flying, you're loosing currency and there's very few airlines flying the 717 for you to move to.
Airlines plan recruitment well in advance. Chances are jobs 6-12 months down the line are being recruited for. If the worst were to happen you're out of a job and before you've had a chance to apply your already 6-12 months without currency and the airlines don't like this.