helping to keep/help to keep

[anhnha]

Its insurance arm is also a huge holder of Japanese government bonds, indirectly helping to keep interest rates low on Japan's mountain of sovereign debt, while its postal service is a political asset that employs more than 200,000 people.
More:Japan govt aims to list Japan Post in three years | Reuters
Can I replace the bold phrase by the following?
"indirectly help to keep interest rates low on Japan's mountain of sovereign debt"
Is there any grammar rule related to it?

[5jj]

Can I replace the bold phrase by the following?
"indirectly help to keep interest rates low on Japan's mountain of sovereign debt" No
Is there any grammar rule related to it?

A participial phrase is what is required here, not a finite verb without a subjct.

[anhnha]

Well, thank you!
I have searched the phrase "participial phrase" and found a great site discussing about this. It is here:The Participle Phrase