As already pointed out in your other thread, AFAIK there is no public information available on the exact nature of the two mentioned specific vulnerabilities. So unfortunately I don't see any way to reproduce the attack vectors and to directly verify if your AEM environment is still vulnerable for these exact issues. While you could test your application for some kind of XSS, this would still not give you any insights for these two specific vulnerabilities. XSS is a very broad field. I tried to find some more details about the nature of the vulnerabilities by their CVEs (as you probably did as well) but was unable to find any public source for it.
I've already outlined how to verify the version (incl. SP and CFP) that is installed on your AEM instance. That's one first and strong indicator that your environment should no longer be vulnerable to these two specific attack vectors. However, in IT security there is no way to guarantee a 100% secure system.
The rewrite rules that you shared from your dispatcher configuration provide some level of protection against certain XSS attacks. However, the field of XSS is very wide and there may still be other attack vectors that could possibly get past these simple rewriting rules. (Please note: while mod_rewrite can help to provide a certain level of basic protection, it is not a dedicated security tool.)
If you have enhanced security requirements (as often seen for customers from e. g. the financial sector), I recommend to:
Keep your overall software stack as up-to-date as possible. This does not only mean AEM but also your operating system, your Java runtime (JRE), 3rd party libraries that you are using, etc. In this context I would also recommend to evaluate if you want to upgrade AEM to a more recent version (6.5 for on-premise). According to Adobes end of life matrix, AEM 6.2 has run out of core support two years ago and even extended support ended last month (April 2021). So there will be no additional updates from Adobe for your specific version of AEM. If you really care about security, running an unsupported AEM version is probably one of the bigger security concerns you should look at. The very least that I would recommend is to upgrade to the latest available CFP for AEM 6.2 (SP1-CFP20) which has been released almost two years ago.
Evaluate some kind of Web Application Firewall (WAF). A popular choice I've seen in projects is mod_security with the OWASP Core Rule Set (CRS). The rule set contains protection against a wide range of attack vectors, including XSS. It's not AEM-specific but a generic solution. Be aware that depending on your application and the desired level of security, it may take quite some effort for initial setup and continuous monitoring, adjustments, fine-tuning and maintenance.
Perform security and penetration tests on your environment and application. There are 3rd party vendors that offer services to test your application and environments. Please note that in my practical experience, I've rarely (if at all) seen a security audit that found product related issues within AEM. Almost all findings could be tracked down to custom application development performed by the project. In addition to that, I am aware of two additional AEM-specific resources that may help you testing your installation on your own: