Since both your identical Toshibas are having the same difficulty with HiFi audio tracking on these specific tapes, you're probably dealing with a worst-case incompatibility scenario. Your Toshibas are aligned to mostly track HiFi on one end of the spectrum, while your sports tapes were recorded on machines that laid down HiFi tracks on the opposite end of the tracking spectrum. This HiFi incompatibility is unfortunately quite common, and one of the most difficult issues to resolve when archiving old VHS to digital. The VHS HiFi audio standard was a lousy kluge, all but guaranteed to cause massive tracking issues from VCR to VCR, so there's little recourse in trying to make any particular VCR more compatible with the hifi tracks of any particular tapes.
In the old days, a few extremely skilled techs were able to skew a VCRs HiFi tracking alignment to favor specific tapes, without messing up the video tracking, which is what you basically want done. But this compromise alignment was rarely successful, and rarely held for very long. If you are quite sure all of your sports tapes were made on the same VCR and all have the same HiFi alignment, you could bring one of your Toshibas and one of those tapes to a tech and ask them to calibrate the Toshiba's HiFi alignment for optimal tracking of only those tapes. But finding such a tech locally isn't easy, and shipping the VCR to a distant tech can be pricey. Plus, no guarantee for how long the new alignment would hold, and that Toshiba would then be incompatible with all your other tapes. Skewing the HiFi may not be possible without messing up the video tracking, which might in turn conflict with the Toshibas noise reduction system, which would defeat the whole point of using this upscale Toshiba in the first place. You see how tricky things can get once you start tampering.
What is it about the Toshiba 808 playback that you prize so highly? The DNR? Rather than spend a fortune chasing down an elusive realignment, you might be better off trying a couple of other VCR brands with DNR that could be a better HiFi tracking match for your sports tapes. Perhaps a JVC DVHS, which you could easily resell at little to no loss if it doesn't give results you want. Also check Craigs List for standard Sharp, JVC, Mitsubishi and Panasonic 4-head HiFi VCRs: some of these perform remarkably well with hifi tracking, don't compromise much on the video, and cost only $20. Worth a try: if nothing else, testing these sports tapes on other VCR brands will quickly reveal whether the bigger problem is your Toshiba VCRs or the tapes themselves. If the tapes exhibit HiFi audio problems on most other VCRs, they were likely recorded on a poorly-aligned VCR to begin with, and might be impossible to track perfectly on anything but that original VCR. Meaning you should set your Toshibas to linear audio playback, and tolerate the drop in quality from HiFi (those HiFi tracks are substandard and will never play correctly).
At this point, with the best classic VCRs aging rapidly and qualified techs scarcer than heart surgeons, we kind of need to compromise and "settle" when it comes to VHS archiving. Sometimes you have to choose whats more important on specific tapes, their audio or their video, and use a VCR that will give the best playback for that aspect. For a music video, you might prioritize the audio, for sports the video action is probably more critical. Unless you can find a tech who can successfully modify one of your Toshibas, I think you might want to adopt a "glass half full" attitude (i.e., things could be worse: the audio track for sports is usually not that critical, while a collection of movies or concert videos would be a huge problem).