Issues opening IDML file having XML tagging/structure

What do you mean by "IDML file parses"?

 

The only tool they can "parse" IDML file is InDesign. 

Technically true, but there are many translation environments/tools/language management systems that can interpret and write IDML. So I'm guessing that JayShree means "it opens up successfully in my translation tool." Happens all the time that someone exports an IDML that crashes InDesign. That's often because there is some bit of format-tagging or format-painting that has not been completed in the translation tool. 

JayShree, what tool are you using? Also, did you look at @Laubender's comment above? 

One strategy I use to troubleshoot bad IDML export is to make a project TM with only the strings that are in the IDML source document that crashes upon export. Then I take the source IDML and delete the last half of the document in InDesign (that is, delete pages 21-40 of a 40-page doc) and re-export the IDML. I can then drop that IDML into The Tool I'm Using That Day, apply the TM, and then export IDML right away. If that exports successfully and opens in InDesign, I know that there's a problematic element somewhere in pages 21-40. If it fails, I know the problem is somewhere in the first half, so then I can try the same process again with pages 1-10. 

This doesn't always work, of course, if the problem with the file is structural. But if your document is 100% XML-tagged, you can try a similar strategy by simply untagging the whole thing, exporting IDML, and then reapplying TM.  If that works, it proves that your XML tagging is actually the source the problem.

But the resolution to your issue isn't likely to be found here at the Adobe Community - it's going to be the supplier of your translation tool. (Unless I happen to know your tool well, in which case I might be able to tell you to e.g. "open the IDML filter properties and uncheck thus-and-so".)