Pass parameter vale in Aliases?

Try using that alias outside the function to assign a variable value and hard code the value in.  That will help narrow down the issue.

OK, first of all, everything I'm saying after this sentence is based upon guess. 

My GUESS... is that you're using a JavaScript project.  In the JavaScript implementation in TestComplete, there are limitations on operating on properties that are accessed via index, like wValue in your code example.  In these situations you need to use $set and $get to work with properties that have indices.

Change your code to the following:

function FXConnectRFSClientAllin(Val)
{
var intValue= Aliases.jp2launcher.JideSystemShell.Orders.exec_orders.RootPane.null_layeredPane.null_contentPane.SessionDetailsTabbedPanel.Panel.JideTabbedPane.BusyComponent.JXLayer.MultiOrderCardPanel.RFS_Competitive.JS_RFSOrderDetails.$get('wValue', Val)
return intValue
}

One other item of note... you might want to redo your Aliases.  There are a lot of aliases in your string that appear to be just place holders in the hierarchy.  If you're not interacting directly with "null_layeredPane", it doesn't need to have an Alias.  It is probably mapped and that can remain, but you might want to look at "compressing" your Aliases into more usable strings.  See https://support.smartbear.com/testcomplete/docs/testing-with/object-identification/name-mapping/overview.html#about-the-mapped-objects-and-aliases-trees

I guess 0,15 is row and column number to get value using wValue(row,column) method.

If i assume correctly, then you have to pass two parameters in order to get the value, as like below.

function FXConnectRFSClientAllin(rowValue,ColValue)
{
var intValue= Aliases.jp2launcher.JideSystemShell.Orders.exec_orders.RootPane.null_layeredPane.null_contentPane.SessionDetailsTabbedPanel.Panel.JideTabbedPane.BusyComponent.JXLayer.MultiOrderCardPanel.RFS_Competitive.JS_RFSOrderDetails.wValue(rowValue,ColValue);
return intValue
}