Been at FR for a number of years and not heard any rumours like this, but I am aware of a person that did the initial ground school and sim but not the base training, so really had'nt completed the "type rating"to a level it could be endorsed on the license, they started again from scratch.
As far as I am aware, the amount of JAR type 25, i.e multi pilot types does not effect the type rating process , infact, if it was your first multi-pilot type you would have no JAR 25! But obviously it;s easier to do the sim if you are used to being in a multi crew environment, if not do a JOC first.
Obviously if you are prepared to pay for another type rating on the basis you get a job... well that's a whole different scenario.
Pays to read between the lines.
If you have solid experience on Jar 25 types, like 1500 heavy turbo prop then you buy a rating, you stand a reasonable chance "independently self typing" if you don't have this level of experience it may be worth attaching yourself to a company that can guarantee a job at the end of the process, assuming you get through selection in the first place.