3: The match is postponed

This obviously, isn't the best idea, but the truth is that the WWE have put a lot of stock into this match, so to see if vanish without a trace isn't good.
So, why not wait? Wait until Strowman is 100%, and have the match, with the same stipulations at a later date.
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If it was hosted on RAW, the company could advertise it well in advance, which would certainly help their falling viewerships.
The WWE Universe already got to witness a free-TLC match last week on RAW between the Constable and Seth Rollins, in what was a highly entertaining match.
Having another, whilst it may be a tad too soon, would certainly be entertaining, and there's no point rushing Strowman into TLC if there's a genuine risk to his health if he competes.