Syntax highlighting for injected language into XML attribute value is not working

I am contributing to the Intellij plugin for the AEM platform (actual version: https://github.com/aemtools/aemtools/tree/v0.9.2). There are XML files where I injected custom language into some attribute values. There lexer and parser for the custom language. Example of XML file:

<?xml version="1.0" encoding="UTF-8"?>
<jcr:root xmlns:sling="http://sling.apache.org/jcr/sling/1.0"
          xmlns:jcr="http://www.jcp.org/jcr/1.0"
          jcr:primaryType="sling:OsgiConfig"

          some.attribute.first="value"
          some.attribute.isSecond="{Boolean}true"
          some.attribute.array="[attr.val1,attr.val2]" />

Value, {Boolean}true, [attr.val1,attr.val2] - are the code of my custom injected languge. I do injection implementing MultiHostInjector inteface.

class JcrPropertyInjector : MultiHostInjector {
  override fun elementsToInjectIn()
      : MutableList<out Class<out PsiElement>> = mutableListOf(XmlAttributeValue::class.java)

  override fun getLanguagesToInject(
      registrar: MultiHostRegistrar,
      context: PsiElement) {
    val attributeValue = context as? XmlAttributeValue ?: return

    val attributeName = attributeValue.findParentByType(XmlAttribute::class.java)
        ?: return

    val parentTag = attributeName.findParentByType(XmlTag::class.java)
        ?: return
    val psiLanguageInjectionHost = context
        as? PsiLanguageInjectionHost
        ?: return

    //some logic to check suitable attribute name
    registrar.startInjecting(JcrPropertyLanguage)
    registrar.addPlace(null, null, context, TextRange.create(1, attributeValue.text.length - 1))
    registrar.doneInjecting()
  }
}

I decided to have my own highlighting of this custom injected language in the XML attribute value. I implemented ColorSettingsPage interface and registered it as an extension as well. As a result, in the Setting -> Editor -> Color Scheme -> JCR Property Language I see highlighted demo XML text, however, on the real file, injected language in the xml attribute value is highlighted as XML Injected Language Fragment (with green background).

I tried to implement EmbeddedTokenHighlighter too, but it didn't give any result.  

Could you please help me to understand what did I miss or what should I implement to highlight injected language? Maybe some HighlightVisitor or something else?

Let me know if I need to provide more details.