Actually, partitions under 32MB are same in TOS and DOS . Only above it starts to differ - because different logical sector sizes.
But that means not that it is accessible for TOS - I guess that it needs to be removed for TOS because it is boot partition for MS DOS.
The whole combination is something very special, and no wonder that Mint has problem with it.
I don't think that there is some tool for this case - with Mint.
Basically, what you have are very old drives, as I see. Question is, is it worth to invest time for thinkering solution for this - that may be hard case. Old disks will not last long.
I think that best solution would be to go one some modern storage, Flash card based. Then you can have diverse medias for Mint, for Supercharger and for TOS. Not to mention much larger capacities - GB-s, not 100 MB and like ...
Something more: tool removes L, because TOS can not access it - then why need to remove ? There is L, but not accessible - that is not so big problem.
What happens when you run Mint without that L removal tool ?
Famous Schrodinger's cat hypothetical experiment says that cat is dead or alive until we open box and see condition of poor animal, which deserved better logic. Cat is always in some certain state - regardless from is observer able or not to see what the state is.