Here are a number of sources :
Australian Veterinarian is one of many that mentions that the p. vitticeps does not grow back it's tail.
The tale of two tails! This is an interesting one from the vault. A few years ago a large male eastern water dragon (Intellagama lesueurii ) was brought in having been hit by a car. Sadly his...
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Quote : Not all dragon species can regrow their tails. Australian species such as painted dragons (Ctenophorus pictus) and two lined dragons (Diporiphora bilineata) can BUT THE BEARDED DRAGON [ POGONA ] SPECIES CAN NOT..
Other sources :
https://www.allcreaturesanimalhospital.com/pdf/reptile-bearded-dragons/bearded-dragon.pdf
Quote : It is important that you make sure the bearded dragon is not missing any body parts. Bearded dragons do not regrow their tails, toes, or limbs. So if your bearded dragon is missing something, it will not grow back. With this being said it is not unusual for a beardie to be missing a few toes or the very end of it's tail (many times bearded dragons will fight over females and minor injuries like this occur.
Symptoms blackening of tail, starting at the tip tail does not shed Cause tail trauma incomplete shed cutting off tail circulation Treatment Bearded dragons can’t regrow their tails, so a tail injury is relatively serious. If you believe your dragon… Continue Reading →
reptifiles.com
Quote " Bearded dragons can’t regrow their tails, so a tail injury is relatively serious. If you believe your dragon has tail rot, take him/her to the vet. Depending on the severity of the issue, the tail may be saved. Most likely, however, your vet will either recommend surgery or letting the tip fall off on its own."