This doesn't seem to be possible. India made two tours of Australia in the 1980s:

* [1980-81](https://static.espncricinfo.com/db/ARCHIVE/1980S/1980-81/IND_IN_AUS/)
* [1985-86](https://static.espncricinfo.com/db/ARCHIVE/1980S/1985-86/IND_IN_AUS/)

On these tours, three matches were played in Tasmania:

* [A first class match from 11-13 December 1980](https://static.espncricinfo.com/db/ARCHIVE/1980S/1980-81/IND_IN_AUS/IND_TAS_11-13DEC1980.html); Kapil Dev did not play in this match.
* [A one day match on 14 December 1980](https://static.espncricinfo.com/db/ARCHIVE/1980S/1980-81/IND_IN_AUS/IND_TAS_14DEC1980.html); Kapil Dev did play in this match, but it was at the [NTCA Ground](https://en.wikipedia.org/wiki/NTCA_Ground) which is not next to the river. Kapil Dev _did_ hit a six in this match, so possibly there is some exaggeration of the story happening.
* [A first class match from 20-23 December 1985](https://static.espncricinfo.com/db/ARCHIVE/1980S/1985-86/IND_IN_AUS/IND_TAS_20-23DEC1985.html); this match was abandoned without a ball bowled.

For completeness, I also looked at [India's 1991-92 tour of Australia](https://www.espncricinfo.com/series/india-tour-of-australia-1991-92-62295/match-results); the only match played in Tasmania was [the ODI against Australia in which Kapil Dev did play but no sixes were hit](https://www.espncricinfo.com/series/benson-hedges-world-series-1991-92-60921/australia-vs-india-3rd-match-65481/full-scorecard).