If a really big dump happens, many HODLers will be in trouble.
If a bear market starts, then even 5 days of delay is no biggy, these institutional investors will be still on great profit. And they surely have some smart analysts on their payroll which can tell clearly it's bear market or just another dip.
Then, I expect that at least some of these institutional investors have no intention to sell even if bear market starts. They are not traders/speculators and in 2-4 years the bull market will get them on even greater profit.
Again, I think that they have analysts that can tell how big is the chance the bull run continues after 100k and advise them to buy or not. Or to sell.
If the institutional investors keep buying, the current bull run will be longer and the bear market will no longer be as bad as the previous ones. It's just a feeling though, but others have already said that this bull run is going to be different.