The participle is OK.
The using of pronoun «свои» is incorrect here. You should say: «Все его деньги инвестированы…».
After «инвестированы в» accusative should appear: «…инвестированы в безопасные финансовые продукты»
«Дети развлечены клоуном» is “The children have been amused by the clown”. Though the phrase sounds very strange.
You shouldn’t use the passive participle here. An active verb is better:
“The children are amused by the clown” — «Детей развлекает клоун».
I don’t know why…