Thanks for reporting this. There are two issues, which I have corrected.
The program ppmlhdfe is not an official Stata program, therefore, asdocx was unaware of that. I have added it to the supported packages inside asdocx
The ppmlhdfe uses a matastrict on condition, that would cause the asdocx package to throw errors. I have fixed that too.
You can now update asdocx and restart Stata