I did a fairly deep dive into this (and actually got accepted into a programme at one of the Designated Organisations but haven't gone through with it yet).
It does seem that many (most?) of the accelerator/incubators are pay-to-play. Some are more upfront about this than others. Techstars Toronto would be a notable exception obviously.
I suspect there's a little bit of this pay-to-play at work in some of the angels and funds also who are Designated Organisations, but I can't say that for certain.
The other thing I've gleaned is that the process currently takes a LONG time - like 1 year plus.
There's a couple forums you can search for that active ongoing discussions from applicants.
KJ8T but I've never made my own QSL card...