cant access index.php anymore if set index.htm directoryindex in htaccess HELP!

hello im trying to set in htaccess file the DirectoryIndex field to access before the index.htm file than the index.php cause i want to create an intro page with an ENTER link to go to the index.php, but when i set the index.htm priority i cant access anymore the index.php page, this mean that i cant access it directly or clicking the enter link that link to it, cause accessing to the /index.php page will send to the index.htm page loading the root domain, so i cant access anymore the wordpress index.php

This is totally caused by wordpress, cause if i set the index.pho file before the index.htm file i can still open both page

Its like wordpress index.php page check the htaccess priority and if found a different index page to have more priority start loading it

This is not a problem of the server, cause other folder with phpbb forum or html files follow correctly the htcaccess priority and load all files, is just like WORDPRESS DONT ALLOW TO LOAD MULTIPLE INDEX files.

Someone know how to fix this in order to load the index.htm file and still leave access to the wordpress index.php page or a workaround to do this?

Please help i really need to do this as soon as possible and im looking all the web to find a fix.