Looking for advice how to correctly configure PWM dimming with Mean Well LDH-45A-1050 device
I assume you want to use a PWM controller. 

There are 2 criteria the controller must meet.


The signal voltage must be between 2v and 8v.
The frequency of the the PWM single must be between 1Khz and 10Khz.


1 is easy to find.
2, many controller ads do not specify the frequency.

So I am guessing the "couple PWM devices" you tried had a PWM switching frequency below 1Khz or more likely above 10Khz.  A quick look on eBay the ones I found that specified the frequency,  it was above 10Khz (13Khz &amp; 15Khz).