What is the motivation for the WHO-bashers?

It's interesting to note just who is leading the current ill-advised charge against the World Health Organization (WHO).
Well, Donald Trump - no surprise there. Trump will adopt any policy that shifts attention from his own spotty and lacklustre performance during the COVID-19 outbreak. He is pathologically incapable of taking blame or responsibility, and has an almost equally pathological hatred of internationalism in any form. However, he does not want to be seen directly blaming Chinese autocrat Xi Jinping, for whom Trump has a clear respect, as he does for many of the world's autocrats, so the WHO makes a convenient scapegoat. Besides, sidelining the organization would mean he does not have to bother figuring out the pronunciation of its director-general, Tedros Adhanom Ghebreyesus, not to mention saving  over $400 million which can be used to pursue his America First agenda.
In Canada, though, the WHO detractors are mainly limited to federal Conservative leader Andrew Scheer and Alberta Conservative premier Jason Kenney, both of whom have been outspoken in their criticism of the international advisory body, as well as of Canada's Chief Public Health Officer, Dr. Theresa Tam, who - shock horror! - had the pusillanimity and temerity to accept the advice of the widely-respected world health authority.
So, what is their justification and motivation? Partly, it is just puerile partisan politics - as Conservative leaders, they feel they have to be seen to be opposing anything the Liberal leadership is saying, whether or not they believe or care about it in their heart of hearts. It is the ugly side of two-party oppositional democracy.
Other than that, though, I am really not sure. A sneaking respect for Donald Trump, perhaps? Who knows? It certainly seems counter-productive and in poor taste to be finger-pointing and scoring petty political points at a time when national unity has never been more needed. Any attempt to discredit or knee-cap our public health officials and agencies has to be dangerously ill-conceived at any time, but particularly do in the midst of a major national and international health emergency.
Is there any significance to the fact that most of the detractors are way on the right of the political spectrum? (The only non-Conservative critic I can think of is former Liberal justice minister Irwin Cotler, although his beef is much more with China than with WHO or the Canadian health agencies.) I don't know the answer to that either. I just wish they would stop. There will be plenty of time for recriminations and politicking later. Let's just get through this national emergency first.