We can stop questioning whether DNA exists or not:
https://www.cbc.ca/news/canada/toronto/police-seek-dna-samples-in-varaschin-case-1.994483
"The Orangeville Police Service and the Ontario Provincial Police said that "
DNA was recovered" during the course of the eight-month investigation."
LE collected voluntary samples of DNA so I doubt it was a bluff. But I have often wondered in the past 10 years, what happened with the DNA? Especially with the link you posted regarding technology to help differentiate between one contributor and another. That piece of information is interesting. Does this mean the DNA they have is mixed with SV? Or mixed with another perpetrator??
Also, as you said
@Gina20 I too was under the impression that this technology was part of some kind of standard forensic procedure. Could it be that since it has been mixed with another profile, it would be too degraded/contaminated for other tests or use in other labs? That would be so disappointing.
Police collecting DNA in Varaschin murder probe
"He said Wednesday it could take up to three weeks to collect the samples, but can't say now long it will take to get the results. Leon says he would expect anyone with nothing to hide to provide a sample."
Ita. Much more plausible. I don't believe there was any attempt made to conceal the body due to the murderer feeling remorse or guilt. IMHO Sonia was hidden for the purpose of buying time and creating distance.