Getting Values Nested within and Object and Comparing with Variable Value

I have a two-part issue.

1) I need to access a list of unique values nested within a complicated object. I am able to output the object via a console.log as such:

console.log(dataStore);

This outputs the following (in part):

`Object
    getResponses: function getResponses(ids)
        arguments: null
    
        caller: null
    
        length: 1
    
        name: "getResponses"
    
        prototype: Object
    
        __proto__: function ()
         
        <function scope>
            Closure
                responseCache: Object
                    12345: gr.Response
    
                    12346: gr.Response
                    etc...
    getImg: function (imageId)
    etc... `

I need a call that gathers the list of values under responseCache: 12345, 12346, 12347, etc. The number of these values may very.

2) I need to create a conditional statement that compares the value for a variable that is not a part of the object above. For example:

variableX = variableXvalue;

if ("variableXvalue" is one of the unique values in "responseCache") {
//then do this
}

Not sure if it matters for the purposes of the question here, but the variableX is in a loop that iterates through attributes on a page. It loops through all matching tags/attributes on a page, and needs to compare those attribute values with the full list of responseCache values each time it loops.

Thank you for considering this question.