Easy answers are no, no and no.
My achievements are all ingame. i.e. i have an achievement layout that the player can go to and see what they have and what they need to do to get the others.
In that achievement layout, i have everything turned way down. For instance, collect 1000 stars is set to 25 for testing. As you said, to make sure everything works as intended.
Now if you have a flag, on a pole, on a mountain, on another planet, THAT will prove difficult to test for, unless you go actually do it.
If you can lower an achievement, DO IT! Just record what it was before, and to make sure you put it at its original value before going live.
As far as the IAP's - as long as everything is set-up, added, saved and linked in the dev console, and everything matches that from in your game, and set to test, your golden.
When you purchase an IAP, the confirmation window will pop-up and let you know: "This is a test. You will not be charged".
But you do know, you can not test with the email/google account you have set as the administrator in google dev console?
My account is blahblah at gmail, for example. I can not test with that account.
I have to test with one of my other 5 google accounts. And the accounts you want to test with have to be set in 3 different places in the dev console. Especially for the IAP's. That you can find under 'settings' and i forget which tab it is, but its at the very bottom of a page. You'll know when you see it.
Now when you test, google game will show a small pop up box at the top of your game screen, telling you that you hit an achievement.
Also, i don't know if it can be done without 1st uploading 1 apk to the dev console and alpha publishing it, but after you build in Intel XDK, you should be able to download the .arm file from the link you get from codova androud/ios build email directly to your phone....on Android. Dont know about ios.
For me, these are just mini-tests. If it looks to be working, the achievements, IAP's and other things, i will upload that new apk to the dev console. I want to be sure that Intel XDK and google dev console are on the same page, so to speak.
And sorry, that was a longwinded answer. Shorter answer: YES, you actually have to get the achievements or do the time based ones also. But as i said, just lower them way down. Or turn them way up...for instance: you have to cross a bridge in a short time, say 15 secs. Hard. Turn it up to 60 secs. Easy.
Again, DO NOT FORGET TO PUT THEM BACK TO THE ORIGINAL.