Multicurrency payment issue with instamojo plugin

Hi! I need some urgent help on this issue which I am facing for over a week. I use Opencart 2.3.0.2 and my payment gateway is instamojo and my default currency is INR. However in our cart we have options for customers around the world to see their cart in many other currency as well. Instamojo only collects payment in INR and does not handle multi-currency.
At the moment, if my value is say Euro 156.23 instamojo picks 156.23 and collected INR156.23 which is wrong and grossly short collected. I have been seeking help from the gateway instamojo for a week and they repeat that they only take the value given by Opencart and nothing more is being done by them.
My question : 1. Is Open cart passing the final invoice value to payment gateway as a number in the currency of invoice of in default currency?
2. Is the value being passed by opencart include both amount and currency?
3. If I need the value passed to be only the value from that stored in default currency of mine which is INR and same as the default and only currency for the payment plugin instamojo, what must I do?
I will greatly appreciate if someone can advice on this urgently. While I have short collected from a customer this way of plugin integration to me seemed disastrous as if the customer were seeing in yen, I would have collected a Billion INR as an error!!
I am no developer but think that there must be a basic check and necessity in Opencart to ensure no plugin is accepted which cannot take both currency and value together. If a plugin only takes value from opencart then the risks are too high on either side. I am unable to prevail on the payment gateway team to understand this atleast as yet!

You can try to ask developer of this module to improve it. If you not get any respond and still facing this issue I can help you... Please write me PM.