If RDI, is it unlikely they knowingly killed their daughter?

Basically, assuming RDI.

The key question i guess is it highly reasonable that JBR seemed dead when she was strangled?

I have never really got clarity on this... Or does no one really know for sure except the perp?

I would also ask if JR would have had basic medical training in Navy??. Of course, he may not have been there then

Thanks in advance :)