The Christian population you focus on wants to go to heaven and be with Jesus when they die. They do not want to be frozen and wait
for a second chance to suffer the miserable lives they made for themselves the first time around.
You will have a hard sell, and in the process will also make cryonics look like a circus.
Think carefully about this, before you attempt it.
The other issue is why do we need more cryonicists? I suppose we could welcome a few thousand more who are committed to trying it, for the right reasons. You might have a valid argument for approaching the unwashed masses, after cryonics is demonstrated to be of some use, via resuscitating people, repairing the damage, and curing them of why they died in the first place. In the interim, you have no reason at all to want more people signed up for cryonics, nor to con them into doing so via rhetoric and false ideology.