The Tk::Balloon doc says for the -balloonmsg option:
If you give it a scalar reference then it is dereferenced before being displayed. Useful if the postcommand is used to change the message.
It seems that it isn't necessary to utilize -postcommand for your problem, using a reference for -balloonmsg should suffice.

In reply to Re: reattaching Tk ballons by eserte
in thread reattaching Tk ballons by Anonymous Monk

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