"likely join" is a correct and usable phrase in written English.
Example: John is likely to join the football team this year.
Mike Pence will most likely join the president on some tour dates like a less-famous opening band, and there will probably be some of those new "USA 45" hats for sale at the Trump merch table.
Gulf countries would likely join the nuclear bandwagon if Iran goes nuclear.
If so, they will likely join the U.S. national team in Mexico City.
European diplomats say Cyprus will very likely join, with or without a settlement.
For months now, Podesta has been telling people that if Hillary decided to run he would most likely join her.
It will most likely join the Nasdaq 100 index, the benchmark index for technology stocks, soon after it begins trading.
Whatever the case, Black and McMickin had likely joined Twitter to speak freely.
So he reasoned that if Ms. Ferenczi's friend retired in 1906, he most likely joined the police force around 1880.
"Your employees likely joined you for the same reasons.
As you can see from Fig. 7, Ni atoms are likely joined in clusters on the whisker surface.
Around the same time, the company will announce participation from some high-profile fashion industry players, too, likely joining as celeb donors.
