Probably not, Malwarebytes does a good job as far as hyper-updating their malware signatures and HitmanPro's behavioral file analysis is one of the best -- if they didn't detect it, Avira is probably just showing false positives. I'd recommend looking at what type of "malware" Avira says it is-- I use Bitdefender and constantly get Trojan.generic when it throws false positives.
You can check for the details about the hidden objects within the scan report. The full AVSCAN reports are located in "C:\ProgramData\Avira\Antivirus\LOGFILES\".
Hidden objects are just an information that something suspicious is going on. It is not a false alert. As some legitim applications (including Windows) use this mechanism to hide files and registry keys and there is no malware detection even with another tool, there is nothing to be worried about.